参考文献 1
CAIY F, ZHENGY, BODELIERP L, et al. Conventional methanotrophs are responsible for atmospheric methane oxidation in paddy soils[J]. Nature Communications, 2016, 7: 1-10.
参考文献 2
SUJ, HUC, YANX, et al. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice[J]. Nature, 2015, 523(7562): 602-606.
参考文献 3
RHEET S, KETTLEA J, ANDREAEM O. Methane and nitrous oxide emissions from the ocean: A reassessment using basin-wide observations in the Atlantic[J]. Journal of Geophysical Research Atmospheres, 2009, 114: 1-20.
参考文献 4
TAMAIN, TAKENAKAC, ISHIZUKAS. Water-soluble Al inhibits methane oxidation at atmospheric concentration levels in Japanese forest soil[J]. Soil Biology & Biochemistry, 2007, 39(7): 1730-1736.
参考文献 5
BARORI, ELVERTM, ECKERTW, et al. Iron-coupled anaerobic oxidation of methane performed by a mixed bacterial-archaeal community based on poorly-reactive minerals[J]. Environmental Science & Technology, 2017, 51(21): 12293-12301.
参考文献 6
KNITTELK, BOETIUSA. Anaerobic oxidation of methane: Progress with an unknown process[J]. Annual Review of Microbiology, 2008, 63: 311-334.
参考文献 7
SEGARRAK E, SCHUBOTZF, SAMARKINV, et al. High rates of anaerobic methane oxidation in freshwater wetlands reduce potential atmospheric methane emissions[J]. Nature Communications, 2015, 6: 1-8.
参考文献 8
RAGHOEBARSINGA A, OL A, PASSCHOONENK T V D, et al. A microbial consortium couples anaerobic methane oxidation to denitrification[J]. Nature, 2006, 440(7086): 918-921.
参考文献 9
ISLAS-LIMAS, THALASSOF, GÓMEZ-HERNANDEZJ. Evidence of anoxic methane oxidation coupled to denitrification[J]. Water Research, 2004, 38(1): 13-16.
参考文献 10
HUS, ZENGR J, BUROWL C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.
参考文献 11
SHENL D, WUH S, LIUX, et al. Cooccurrence and potential role of nitrite- and nitrate-dependent methanotrophs in freshwater marsh sediments[J]. Water Research, 2017, 123: 162-172.
参考文献 12
PADILLAC C, RISTOWL A, SARODEN. NC10 bacteria in marine oxygen minimum zones[J]. ISME Journal, 2016, 10(8): 2067-2071.
参考文献 13
WANGY, HUANGP, YEF, et al. Nitrite-dependent anaerobic methane oxidizing bacteria along the water level fluctuation zone of the Three Gorges Reservoir[J]. Applied Microbiology & Biotechnology, 2016, 100(4): 1977-1986.
参考文献 14
CHENJ, ZHOUZ, GUJ D. Complex community of nitrite-dependent anaerobic methane oxidation bacteria in coastal sediments of the Mai Po wetland by PCR amplification of both 16S rRNA and pmoA genes[J]. Applied Microbiology & Biotechnology, 2015, 99(3): 1463-1473.
参考文献 15
柴风光, 卢培利, 李微薇, 等. 利用硝酸盐和亚硝酸盐同步富集厌氧甲烷氧化微生物的比较实验[J]. 微生物学通报, 2018, 45(4): 762-770.
参考文献 16
HUB L, HEZ F, GENGS, et al. Cultivation of nitrite-dependent anaerobic methane-oxidizing bacteria: Impact of reactor configuration[J]. Applied Microbiology & Biotechnology, 2014, 98(18): 7983-7991.
参考文献 17
HATAMOTOM, KIMURAM, SATOT, et al. Enrichment of denitrifying methane-oxidizing microorganisms using up-flow continuous reactors and batch cultures[J]. Plos One, 2014, 9(12): 1-12.
参考文献 18
ZHUB, VAN D G, FRITZC, et al. Anaerobic oxidization of methane in a minerotrophic peatland: Enrichment of nitrite-dependent methane-oxidizing bacteria[J]. Applied & Environmental Microbiology, 2012, 78(24): 8657-8665.
参考文献 19
LUESKENF A, ALENT A V, BIEZENE V D, et al. Diversity and enrichment of nitrite-dependent anaerobic methane oxidizing bacteria from wastewater sludge[J]. Applied & Environmental Microbiology, 2011, 92(4): 845-854.
参考文献 20
HEZ F, CAIC, SHENL D, et al. Effect of inoculum sources on the enrichment of nitrite-dependent anaerobic methane-oxidizing bacteria[J]. Applied Microbiology & Biotechnology, 2015, 99(2): 939-946.
参考文献 21
HEZ F, GENGS, PANY W, et al. Improvement of the trace metal composition of medium for nitrite-dependent anaerobic methane oxidation bacteria: Iron (II) and copper (II) make a difference[J]. Water Research, 2015, 85: 235-243.
参考文献 22
YANP G, LIM C, WEIG S, et al. Molecular fingerprint and dominant environmental factors of nitrite-dependent anaerobic methane-oxidizing bacteria in sediments from the Yellow River estuary, China[J]. Plos One, 2015, 10(9): 1-14.
参考文献 23
HUS, ZENGR J, KELLERJ, et al. Effect of nitrate and nitrite on the selection of microorganisms in the denitrifying anaerobic methane oxidation process[J]. Environmental Microbiology Reports, 2011, 3(3): 315-319.
参考文献 24
MINGL W, ETTWIGK F, JETTENM S M, et al. A new intra-aerobic metabolism in the nitrite-dependent anaerobic methane-oxidizing bacterium Candidatus Methylomirabilis oxyfera[J]. Biochemical Society Transactions, 2011, 39(1): 243-248.
参考文献 25
HEZ F, CAIC Y, WANGJ Q, et al. A novel denitrifying methanotroph of the NC10 phylum and its microcolony[J]. Scientific Reports, 2016, 6: 1-10.
参考文献 26
HEZ F, WANGJ Q, HUJ J, et al. Improved PCR primers to amplify 16S rRNA genes from NC10 bacteria[J]. Applied Microbiology & Biotechnology, 2016, 100(11): 5099-5108.
参考文献 27
HEZ F, CAIC, GENGS, et al. Mdodeling a nitrite-dependent anaerobic methane oxidation process: Parameters identification and model evaluation[J]. Bioresource Technology, 2013, 147(8): 315-320.
参考文献 28
ETTWIGK F, BUTLERM K, LE PASLIERD, et al. Nitrite-driven anaerobic methane oxidation by oxygenic bacteria[J]. Nature, 2010, 464(7288): 543-548.
参考文献 29
HUS, ZENGR J, BUROWL C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.
参考文献 30
ETTWIGK F, ALENT V, PASSCHOONENK T V D, et al. Enrichment and molecular detection of denitrifying methanotrophic bacteria of the NC10 phylum[J]. Applied Microbiology & Biotechnology, 2009, 75(11): 3656-3662.
参考文献 31
TIMMERSP H A, WIDJAJA-GREEFKESH C A, PLUGGEC M, et al. Evaluation and optimization of PCR primers for selective and quantitative detection of marine ANME subclusters involved in sulfate-dependent anaerobic methane oxidation[J]. Applied Microbiology & Biotechnology, 2017, 14: 1-13.
参考文献 32
HINRICHSK U, HAYESJ M, SYLVAS P, et al. Methane-consuming archaebacteria in marine sediments[J]. Nature, 1999, 398(6730): 802-805.
参考文献 33
HAROONM F, SHIHUH, YINGS, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.
参考文献 34
TIMMERSP H A, WELTEC U, KOEHORSTJ J, et al. Reverse methanogenesis and respiration in methanotrophic archaea[J]. Archaea, 2017, 17: 1-22.
参考文献 35
周京勇, 刘冬秀, 何池全, 等. 土壤中甲烷厌氧氧化菌多样性的分子检测[J]. 生态学报, 2015, 35(11): 3491-3503.
参考文献 36
SCHELLERS, YUH, CHADWICKG L, et al. Artificial electron acceptors decouple archaeal methane oxidation from sulfate reduction[J]. Science, 2016, 351(6274): 703-707.
参考文献 37
陈颖. 厌氧甲烷氧化微生物代谢分子机制及其潜在参与矿物形成机理的研究[D]. 上海: 上海交通大学, 2014.
参考文献 38
FUL, DINGZ W, DINGJ, et al. The role of paraffin oil on the interaction between denitrifying anaerobic methane oxidation and Anammox processes[J]. Applied Microbiology & Biotechnology, 2015, 99(19): 7925-7936.
参考文献 39
ETTWIGK F, ZHUB, SPETHD, et al. Archaea catalyze iron-dependent anaerobic oxidation of methane[J]. Proceedings of the National Academy of Sciences ,2016, 113(45): 12792-12796.
参考文献 40
DINGL J, SUJ Q, XUH J, et al. Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing[J]. ISME Journal, 2015, 9(3): 721-734.
参考文献 41
VAKSMAAA, LÜKEC, ALENT V, et al. Distribution and activity of the anaerobic methanotrophic community in a nitrogen-fertilized Italian paddy soil[J]. FEMS Microbiology Ecology, 2016, 92(12): 1-11.
参考文献 42
SEIFERTR, NAUHAUSK, BLUMENBERGM, et al. Methane dynamics in a microbial community of the Black Sea traced by stable carbon isotopes in vitro[J]. Organic Geochemistry, 2006, 37(10): 1411-1419.
参考文献 43
DINGZ W, DINGJ, FUL, et al. Simultaneous enrichment of denitrifying methanotrophs and anammox bacteria[J]. Applied Microbiology & Biotechnology, 2014, 98(24): 10211-10221.
参考文献 44
HEZ F, GENGS, SHENL D, et al. The short- and long-term effects of environmental conditions on anaerobic methane oxidation coupled to nitrite reduction[J]. Water Research, 2015, 68(47): 554-562.
参考文献 45
HAROONM F, HUS, SHIY, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.
参考文献 46
WEBERH S, HABICHTK S, THAMDRUPB. Anaerobic methanotrophic archaea of the ANME-2d cluster are active in a low-sulfate, iron-rich freshwater sediment[J]. Frontiers in Microbiology, 2017, 8: 1-13.
参考文献 47
VAKSMAAA, JETTENM S M, ETTWIGK F, et al. McrA primers for the detection and quantification of the anaerobic archaeal methanotroph Candidatus Methanoperedens nitroreducens[J]. Applied Microbiology & Biotechnology, 2017, 101(4): 1631-1641.
参考文献 48
DINGJ, LUY Z, FUL, et al. Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell[J]. Water Research, 2016, 110: 112-119.
参考文献 49
VAKSMAAA, GUERRERO-CRUZS, ALENT A V, et al. Enrichment of anaerobic nitrate-dependent methanotrophic Candidatus Methanoperedens nitroreducens archaea from an Italian paddy field soil[J]. Applied Microbiology & Biotechnology, 2017, 101(18): 7075-7084.
参考文献 50
AIM, MOCHIMARUH, KAZAMAH, et al. Development of 16S rRNA gene-targeted primers for detection of archaeal anaerobic methanotrophs (ANMEs)[J]. FEMS Microbiology Letters, 2010, 297(1): 31-37.
参考文献 51
STROUSM, JETTENM S M. Anaerobic oxidation of methane and ammonium[J]. Annual Review of Microbiology, 2004, 58(1): 99-117.
参考文献 52
TIMMERSP H, SUAREZZULUAGAD A, ROSSEMM V, et al. Anaerobic oxidation of methane associated with sulfate reduction in a natural freshwater gas source[J]. ISME Journal, 2016, 10(6): 1400-1412.
参考文献 53
MILUCKAJ, FERDELMANT G, POLERECKYL, et al. Zero-valent sulphur is a key intermediate in marine methane oxidation[J]. Nature, 2012, 491(7425): 541-546.
参考文献 54
WICKLANDK, HAMDANL, ROOZEJ, et al. Iron‐dependent anaerobic oxidation of methane in coastal surface sediments: Potential controls and impact[J]. Limnology & Oceanography, 2016, 61: S267-S282.
参考文献 55
EGGERM, RASIGRAFO, SAPARTC J, et al. Iron-mediated anaerobic oxidation of methane in brackish coastal sediments[J]. Environmental Science & Technology, 2015, 49(1): 277-283.
参考文献 56
HANSELC M, LENTINIC J, TANGY, et al. Dominance of sulfur-fueled iron oxide reduction in low-sulfate freshwater sediments[J]. ISME Journal, 2015, 9(11): 2400-2412.
参考文献 57
RIEDINGERN, FORMOLOM J, LYONST W, et al. An inorganic geochemical argument for coupled anaerobic oxidation of methane and iron reduction in marine sediments[J]. Geobiology, 2014, 12(2): 172-181.
参考文献 58
TORRESN T, OCH L M, HAUSERP C, et al. Early diagenetic processes generate iron and manganese oxide layers in the sediments of Lake Baikal, Siberia[J]. Environmental Science Processes & Impacts, 2014, 16(4): 879-889.
参考文献 59
K ÁNORDI, BOT, SCHUBERTC J. Anaerobic oxidation of methane in an iron-rich Danish freshwater lake sediment[J]. Limnology & Oceanography, 2013, 58(2): 546-554.
参考文献 60
AMOSR T, BEKINSB A, COZZARELLII M, et al. Evidence for iron-mediated anaerobic methane oxidation in a crude oil-contaminated aquifer[J]. Geobiology, 2012, 10(6): 506-517.
参考文献 61
HOLMKVISTL, FERDELMANT G, BOB J. A cryptic sulfur cycle driven by iron in the methane zone of marine sediment (Aarhus Bay, Denmark) [J]. Geochimica Et Cosmochimica Acta, 2011, 75(12): 3581-3599.
参考文献 62
SIVANO, ADLERM, PEARSONA, et al. Geochemical evidence for iron‐mediated anaerobic oxidation of methane[J]. Limnology & Oceanography, 2011, 56(4): 1536-1544.
参考文献 63
BEALE J, HOUSEC H, ORPHANV J. Manganese- and iron-dependent marine methane oxidation[J]. Science, 2009, 325(5937): 184-187.
参考文献 64
HEZ F, ZHANGQ Y, FENGY D, et al. Microbiological and environmental significance of metal-dependent anaerobic oxidation of methane[J]. Science of the Total Environment, 2017, 610-611: 759-768.
参考文献 65
ArslanA, SpethD R, DeG R M, et al. A metagenomics-based metabolic model of nitrate-dependent anaerobic oxidation of methane by Methanoperedens-like archaea[J]. Frontiers in Microbiology, 2015, 6: 1-14.
参考文献 66
FUL, LIS W, DINGZ W, et al. Iron reduction in the DAMO/Shewanellaoneidensis MR-1 coculture system and the fate of Fe(II)[J]. Water Research, 2016, 88: 808-815.
参考文献 67
ETTWIGK F, SHIMAS, VAN P S, et al. Denitrifying bacteria anaerobically oxidize methane in the absence of archaea[J]. Environmental Microbiology, 2010, 10(11): 3164-3173.
参考文献 68
LUY Z, FUL, DINGJ, et al. Cr (VI) reduction coupled with anaerobic oxidation of methane in a laboratory reactor[J]. Water Research, 2016, 102: 445-452.
参考文献 69
蔡朝阳. 潮间带古菌介导的甲烷厌氧氧化过程研究[D]. 杭州: 浙江大学, 2017.
参考文献 70
SCHUBERTC J, FRANCISCOV, TINAL S B, et al. Evidence for anaerobic oxidation of methane in sediments of a freshwater system (Lago di Cadagno) [J]. FEMS Microbiology Ecology, 2015, 76(1): 26-38.
参考文献 71
ONI O E, FRIEDRICHM W. Metal oxide reduction linked to anaerobic methane oxidation[J]. Trends in Microbiology, 2017, 25(2): 88-90.
参考文献 72
WANGF, ZHANGY, CHENY, et al. Methanotrophic archaea possessing diverging methane-oxidizing and electron-transporting pathways[J]. ISME Journal, 2014, 8(5): 1069-1078.
参考文献 73
SHIL, SQUIERT C, ZACHARAJ M, et al. Respiration of metal (hydr)oxides by shewanella and geobacter: A key role for multihaem c-type cytochromes[J]. Molecular Microbiology, 2010, 65(1): 12-20.
参考文献 74
SHIL, DONGH L, REGUERAG, et al. Extracellular electron transfer mechanisms between microorganisms and minerals[J]. Nature Reviews Microbiology, 2016, 14(10): 651-662.
参考文献 75
WANKELS D, ADAMSM, JOHNSTOND T, et al. Anaerobic methane oxidation in metalliferous hydrothermal sediments: Influence on carbon flux and decoupling from sulfate reduction[J]. Environmental Microbiology, 2012, 14(10): 2726-2740.

淡水系统中甲烷厌氧氧化古菌的研究进展

翟俊, 李媛媛, 何孟狄, 马宏璞, 戴元贵. 淡水系统中甲烷厌氧氧化古菌的研究进展[J]. 环境工程学报, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098
引用本文: 翟俊, 李媛媛, 何孟狄, 马宏璞, 戴元贵. 淡水系统中甲烷厌氧氧化古菌的研究进展[J]. 环境工程学报, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098
ZHAI Jun, LI Yuanyuan, HE Mengdi, MA Hongpu, DAI Yuangui. Review on the research progress of archaeal anaerobic methanotrophs in freshwater system[J]. Chinese Journal of Environmental Engineering, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098
Citation: ZHAI Jun, LI Yuanyuan, HE Mengdi, MA Hongpu, DAI Yuangui. Review on the research progress of archaeal anaerobic methanotrophs in freshwater system[J]. Chinese Journal of Environmental Engineering, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098

淡水系统中甲烷厌氧氧化古菌的研究进展

  • 基金项目:

    国家自然科学基金资助项目51478062, 51878093国家自然科学基金资助项目(51478062, 51878093)

Review on the research progress of archaeal anaerobic methanotrophs in freshwater system

  • Fund Project:
  • 摘要: 甲烷厌氧氧化古菌(ANMEs)是甲烷厌氧氧化过程中的重要微生物种群,对自然生境甲烷削减的意义重大,目前研究多集中在海洋系统,而关于ANMEs古菌在淡水系统的研究较少,其相关作用机理和工程应用的研究也尚处于初步阶段。在综合文献及前期研究基础上,介绍了ANMEs为主线的淡水系统甲烷厌氧氧化机制,分析了ANMEs的微生物学特性及地理分布,系统梳理了ANME-2d古菌针对不同电子受体(NO3-、Fe3+、Cr6+等)的电子转移体系研究进展;指出了ANME-2d及其他ANMEs可能根据环境改变而选择不同的电子受体,其相对应的电子转移机制也不同。通过对不同电子受体下的ANME-2d及其他ANMEs在淡水系统中的作用机制进行讨论分析,可为淡水系统甲烷厌氧氧化机制和碳循环过程提供理论依据,并为在工程中应用ANMEs实现同步污染物处理和甲烷削减提供新的思路。
    • 摘要

      甲烷厌氧氧化古菌(ANMEs)是甲烷厌氧氧化过程中的重要微生物种群,对自然生境甲烷削减的意义重大,目前研究多集中在海洋系统,而关于ANMEs古菌在淡水系统的研究较少,其相关作用机理和工程应用的研究也尚处于初步阶段。在综合文献及前期研究基础上,介绍了ANMEs为主线的淡水系统甲烷厌氧氧化机制,分析了ANMEs的微生物学特性及地理分布,系统梳理了ANME-2d古菌针对不同电子受体(NO3-、Fe3+、Cr6+等)的电子转移体系研究进展;指出了ANME-2d及其他ANMEs可能根据环境改变而选择不同的电子受体,其相对应的电子转移机制也不同。通过对不同电子受体下的ANME-2d及其他ANMEs在淡水系统中的作用机制进行讨论分析,可为淡水系统甲烷厌氧氧化机制和碳循环过程提供理论依据,并为在工程中应用ANMEs实现同步污染物处理和甲烷削减提供新的思路。

      Abstract

      Archaeal anaerobic methanotrophs (ANMEs) are key microorganisms in the anaerobic oxidation of methane (AOM), which is of great significance in methane reduction of natural environment. The current researches mainly focused on the ocean systems, while there is little known on the ANMEs are in the freshwater systems. The studies on mechanisms and applications of AOM in the freshwater systems are also rare. On the basis of previous literatures and studies review, the mechanisms of ANME-mediated AOM in the freshwater systems were introduced, the microbial characteristics and geographic distribution were analyzed, and the progress of studies on electron transfer when ANME-2d using different electron acceptors (NO3-, Fe3+, Cr6+, etc.) was systematically reviewed. The ANME-2d, as well as other ANMEs, could select different electron acceptors depending on environment variations which were assigned to different electron-transferring mechanisms. The discussion on the mechanisms of ANME-2d and other ANMEs with different electron acceptors in the freshwater systems could provide the theorical fundament about AOM and carbon cycle in the freshwater, as well as the new insight on using ANMEs to simultaneously reduce CH4 and pollutants in the engineering application.

      CH4是仅次于CO2的第2大温室气体,对全球变暖的贡献已经达到20%[1,2],但CH4产生的温室效应大约是同物质量的CO2的20~30[3],并以每年0.5%~1%的速度增[4]。在自然界中,甲烷的代谢途径主要有甲烷好氧氧化和甲烷厌氧氧化(anaerobic methane oxidation,AOM)2大类,分别由甲烷好氧氧化菌和甲烷厌氧氧化菌介导完成。通常,甲烷好氧氧化被认为是甲烷代谢的主要途径,随后科学家却发现甲烷厌氧氧化削减了超过90%的海洋底层所产生的甲[5,6]和约50%淡水湿地产生的甲[7],使得最终进入大气的甲烷十分有限,因此,AOM在地球C循环过程中占有非常重要的地位,对于维持全球气候稳定也至关重[6,7]

      最早发现的甲烷厌氧氧化是发生在海洋中的以硫酸盐为电子受体的甲烷厌氧氧化(SAMO)[6],随着研究的深入,科学家们发现在淡水环境中存在以硝酸根/亚硝酸根为电子受体的甲烷厌氧氧化(DAMO)[8,9,10]。因此,甲烷厌氧氧化(AOM)的研究环境主要分为2大类:1) 海水中AOM的主要电子受体为硫酸盐或者铁、锰氧化物;2) 淡水系统中存在的硝酸盐或亚硝酸盐驱动的DAMO,也有硫酸盐、铁锰氧化物或者有机物(腐殖酸等)作为电子受体驱动的甲烷厌氧氧化反应。而除了NO2-驱动的AOM是由一种NC10门的Candidatus Methylomirabilis oxyfera细菌介导之外,关于该细菌的自然生境分布检[11,12,13,14]、富集培[15,16,17,18,19]、影响因[20,21,22,23]、电子转移途[20,21,22,23,24]以及分子生物学的研[14,21,25,26,27,28,29,30]较多,其他所有已发现的电子受体驱动的AOM均是由一类隶属于广古菌门的甲烷厌氧氧化古菌(archaeal anaerobic methanotrophs, ANMEs)完成的。这些甲烷厌氧氧化古菌可以在厌氧或者缺氧条件下,以甲烷作为碳源、能源以及电子供体,以硫酸根、硝酸根、铁化合物、锰氧化物、铬氧化物、硒酸盐、AQDS以及腐殖酸等作为电子受体,将甲烷氧化为二氧化碳或者碳酸盐的微生物化学过程。

      对海洋中AOM现象研究已经较多,由于其反应可利用电子受体较为单一(多为SO42-),研究多集中在ANMEs及相关硫酸盐还原菌(sulfate-reducing bacteria,SRB)之间的关系,相互之间的作用机理、反应推断、理论基础和相关环境因素研究也已较为完善。然而,近年来,研究发现淡水系统中(河流、湖泊、湿地、污水处理厂等)也存在ANMEs古菌介导下的AOM过程,且该过程单独或与其他生物反应耦合下的碳、氮、硫元素循环可能对淡水环境碳源与汇格局及过程具有重大意义。相对于海洋较为单一的环境条件,淡水系统环境更为复杂多变,电子受体繁多(SO42-NO2-NO3-、MnO2、Fe3+、Cr6+、硒酸盐、AQDS、腐殖酸等),受人为因素影响大,与ANMEs相关联的微生物的协同作用关系、生物地球化学效应和温室气体减排意义等还很少有研究报道。本研究系统梳理了ANMEs古菌介导下淡水系统的甲烷厌氧氧化过程及相关微生物协同作用机制,旨在为淡水系统甲烷减排及工程技术创新应用提供新的思路。

    • 1 甲烷厌氧氧化反应古菌群

    • 1.1 ANMEs古菌的分类

      AOM反应菌群通常根据系统发育分析情况分为ANME-1、ANME-2(a/b/c)、ANME-3等3类,均属于广古菌[31]。这3类古菌彼此间的进化距离较远,16S rRNA基因序列的相似度仅为75%~92%[6]。即使在ANME-2中,分枝ANME-2a、ANME-2b与ANME-2c相似度也较低,因此常将ANME-2a和ANME-2b合并归为ANME-2a/b[31]。ANME-1与Methanosarcinales (甲烷八叠球菌)/Methanomicrobiales (产甲烷微菌)相似但却独自形成一个新的分[32];ANME-2古菌隶属于Methanosarcinales (甲烷八叠球菌属)[6];ANME-3古菌与Methanococcoides (产甲烷球菌)相[6]。虽然ANME-1、ANME-2、ANME-3属于ANMEs不同的分支,但是都具有在各种生境中厌氧氧化甲烷的能[6]。而随着研究的进行,淡水系统中发现了一种新的ANMEs,被称为ANME-2d。ANME-2d属于ANMEs的亚簇,归属于Methanoperedens科,是ANME-2的一个新的分支——Candidatus Methanoperedens nitroreducens,与其他的ANME-2分支距离较远,ANME-2d被发现可以单独完成在厌氧条件下将NO3-还原成NO2-并同时氧化CH4的过程(nitrate-dependent AOM,N-AOM) (表1)[6]。HAROON[33]进一步通过宏基因组和转录组学分析表明ANME-2d确实只能将NO3-还原为NO2-。ANME-2d后来也被命名为GOM Arc I和AOM-associated archaea (AAA)[34]。ANME-2d也是自然界中唯一被发现可以利用NO3-作为电子受体进行AOM的古菌微生物,因此,在富含NO3-的淡水生态系统中,ANME-2d参与 N-AOM过程对淡水生态系统的碳、氮循环尤为关键,这也是近年来学者的研究热点之一。

      表1 甲烷与不同电子受体反应的吉布斯自由能

      Table 1 Gibbs energy of reactions between methane and relevant electron acceptors

      不同电子受体进行甲烷厌氧氧化的反应式自由能ΔG/(kJ·mol-1)
      5CH4+8MnO4+24H+→5CO2+8Mn2++22H2O-1 028.1
      3CH4+8NO2-+8H+→3CO2+4N2+10H2O-928.0
      3CH4+4Cr2O72-+32H+→8Cr3++3CO2+22H2O-878.8
      5CH4+8NO3-+8H+→5CO2+4N2+14H2O-765.0
      CH4+8Fe3++2H2O→CO2+8Fe2++8H+-454.6
      CH4+4AQDS+3H2O→HCO3-+H++4AQH2DS-41.0
      CH4+SO42-HCO3-+HS-+H2O-16.6
    • 1.2 ANME-1/2(a、b、c)/3古菌生理特性及自然生态分布

      ANME-1/2(a、b、c)/3均可介导完成海洋或淡水环境中的SAOM过[6]。ANME-1具有典型的杆形细胞形态,且在紫外光下能自发荧光,这是含有辅酶F420的产甲烷古菌的显著特[35]。ANME-1和ANME-3既可以单细胞形式存在,也可与硫酸盐还原菌(SRB)以共生体的形式存[35]。ANME-2则往往与硫酸盐还原菌(SRB)以外壳型或者混合型共生体存[35]。ANME-1/2(a、b、c)/3均是产甲烷古菌的进化分支,但到目前为止,还未获得任何单一ANMEs的纯培养[35]。ANME-1/2(a、b、c)/3微生物的生长缓慢,倍增时间长,一般为2~7个月,因此,富集时间长且难度大,限制了ANMEs的生理特性研[36]。有研究应用高甲烷分[37],也有研究通过添加石蜡油来增大甲烷的溶解度从而提高AOM反应速[38]

      FISH处理后,不同类型ANMEs的形[39,40]如图1所示。

      图1
                            FISH处理后不同类群ANMEs的形态

      图1 FISH处理后不同类群ANMEs的形态

      Fig. 1 Morphology of different groups of ANMEs after FISH treatment

      ANME-1/2(a、b、c)/3多分布在海洋冷泉区域,在淡水系统中,主要分布在极端环境如火山口、冰原、温泉等。这些微生物均为严格厌氧微生物,均不能在有氧的环境中生存,因此,到目前为止,并未在任何有氧环境中发现ANMEs的存在,其原因可能是由于ANMEs中含有对有氧环境极为敏感的[6]。ANME-1/2(a、b、c)/3主要分布特性如表2所示。

      表2 ANMEs分布及生理特性

      Table 2 Distribution and physiological characteristics of ANMEs

      古菌群隶属科目或相似科目发现区域特性
      ANME-1相似Methanosarcinales (甲烷八叠菌)/Methanomicrobiales (产甲烷微菌)火山口,深海等长方形,含有辅酶F420
      ANME-2a/b/c隶属Methanosarcinales (甲烷八叠球菌属)冷泉区域,黑海,部分淡水湿地,垃圾填埋场等球菌,与硫酸盐还原菌(SRB)形成混合细胞团且覆盖有机质膜(机理不清楚)
      ANME-3相似Methanococcoides (产甲烷球菌)极端环境(冰原或温泉等),火山口与SRB形成贝壳状细胞团
      ANME-2d隶属于Methanoperedens淡水环境如湿地、土壤、稻田、湖泊、河流、污水处理厂等不规则球菌,直径为1~3 μm左右
    • 1.3 ANME-2d古菌自然生态分布及生理特性

      ANME-2d古菌在自然界中发现较晚,但被发现广泛存在于各种淡水生境中,包括湿地沉积[8]、土壤和稻[40,41,42]、湖泊和河[40,41,42]以及污水处理[43]等。ANME-2d隶属于Methanoperedens科,为不规则球菌,直径为1~3 μm左右,一般以族群状态存在,最适温度为22~35 ℃、最适pH为7.0~8.0[8,10,27,33,44,45]。2006年,研究人员首次通过接种淡水沉积物在生物反应器中富集得到ANME-2d和可以还原NO2-N2并同时氧化的CH4M. oxyfera细菌的混合富集培养[8,10,27,33,44,45]。随后HU[29]也富集到含有ANME-2d古菌的培养物并且推断ANME-2d可能只能将硝酸根还原为亚硝酸根或者相比亚硝酸根ANME-2d古菌更优先利用硝酸根。HAROON[33]研究表明ANME-2d只能将硝酸盐还原为亚硝酸盐,而无法再继续将亚硝酸盐还原为氮气。因此,ANME-2d往往是与M. oxyfera共存于环境之中。但最新研究发现,ANME-2d具有解除由于NO2-浓度过高而产生的毒副作[10]。WEBER[46]在丹麦日德兰低硫高铁的Ørn湖的淡水沉积物中检测到了AOM活性,且证明了ANME-2d古菌主导完成了SAMO或Fe-AOM,也可能同时完成了SAMO和Fe-AOM。因此,ANME-2d古菌不仅存在于高硝酸盐环境中,在低硫高铁等其他电子受体丰富的淡水环境中也存在,这进一步佐证了ANME-2d对于淡水系统中甲烷排放控制的重要性。

      ANME-2d同样具有生长缓慢,倍增时间长等特点,难以进行纯培养物的富集和分离。HU[29]采用含淡水湖泊沉积物、消化污泥和活性污泥组成的混合污泥得到ANME-2d富集培养物,推断ANME-2d存在于一些淡水沉积物中。VAKSMAA[47]以意大利水稻田作为接种污泥经过2年的富集培养获得了含有ANME-2d的稳定富集培养物;ANME-2d的最大丰度达到系统总微生物的22%左右;宏基因测序结果表明ANME-2d含有反向产甲烷的以及硝酸盐还原的所有功能基因。研究人[48]在使用CH4作为燃料的微生物燃料电池(MFC)中研究发现MFC装置可以将ANME-2d古菌与M. oxyfera细菌分开。此外,为了进一步研究ANME-2d在不同生境中的分布以及丰度,提高检测手段以及灵敏度,进一步开展了ANME-2d的引物和探针的研[26,31,35,49,50]

      目前的研究通过分子生物学以及系统发育分析等手段证明了ANME-2d确实可以存在于多种生态环境中,但关于其作用机理及相关生态学意义的研究较少。由于ANME-2d在淡水环境中的广泛存在性,其对于全球淡水生态系统碳循环及温室效应的影响可能被严重忽视。

    • 2 ANMEs作用机制与电子转移途径

      与甲烷好氧氧化相比,在淡水系统中的甲烷厌氧氧化的研究较少。但是在淡水和陆地生态环境中,硫酸盐的浓度远低于海洋环境,且电子受体的种类也比较丰富。现在已发现的AOM根据电子受体类型主要可以分为以SO42-为电子受体的甲烷厌氧氧化(sulfate-dependent AOM,SAMO)、以NO3-/NO2-为电子受体的反硝化型甲烷厌氧氧化(denitrification anaerobic oxidation of methane,DAMO)和以金属氧化物(如Fe2O3和MnO2)为电子受体的甲烷厌氧氧化(metal-dependent AOM,metal-AOM) 3种类型。而研究表明,淡水系统中确实存在ANMEs古菌介导下的AOM现象,这使得ANMEs在淡水生态系统中电子受体选择机制成为当下ANMEs相关研究的热点之[51]

    • 2.1 淡水系统中ANMEs的电子受体选择机制

    • 2.1.1 适用于ANME-1/2(a、b、c)/3的电子受体

      SAMO被认为是连接全球碳硫循环的重要环节,研究表明ANME-1、ANME-2a/-2b/-2c、ANME-3均可驱动SAMO[6]。一般认为,SAMO主要存在于SO42-浓度较高的海洋沉积物环境中,在淡水系统中,当硫酸盐浓度低于0.2 mmol·L-1时SAMO反应将不存在;但是在硫酸盐较低的陆地和淡水生态系统等环境中均发现存在SAMO现[52]。SEGARRA[7]在淡水湿地中也发现硫酸盐电子受体为主导下多种电子受体共同驱动的AOM过程。因此,硫酸盐浓度可能不是制约SAMO过程的关键影响因素。一方面,古菌ANME-1、ANME-2和ANME-3通常与硫酸盐还原菌(SRB)形成密切的共生关[6,51],ANMEs古菌活化CH4,将电子传递给SRB,SRB进一步还原SO42-。另一方面,近年来MILUCKA[53]发现,ANMEs可单独实现甲烷厌氧氧化并将SO42-还原为硫单质(S),从而证明了SAMO不需要SRB协同作用。

      以Fe(III)为电子受体的Fe-AOM在淡水系统中广泛存[5,54,55,56,57,58,59,60,61,62]。2009年,BEAL[63]在湖底沉积物中发现了有微生物以Mn(IV)和Fe(III)作为电子受体对CH4进行厌氧氧化的现象,并推断ANME-1、ANME-3可能主导了该AOM反应过程。2013年,有学者研究淡水系统湖泊沉积物中甲烷厌氧氧化活性,证明了Fe-AOM反应在淡水系统中的存[59]。此外,SCHELLER[36]通过向含有ANME-2a和ANME-2c的SAMO富集培养物中分别添加铁的配合物(柠檬酸铁和乙二胺四乙酸铁)作为电子受体的体系中观察到了AOM现象,表明ANME-2a古菌和ANME-2c古菌可以Fe3+作为电子受体。

      金属矿物在反应自由能上要远大于硫酸盐(表1),在富含金属矿物质的矿山区域、地下潜水等区域,Metal-AOM可能比SAMO更易发生并起到主导作用。但是由于金属氧化物多以固体形式存在,在水体中溶解度非常小,反应的发生可能存在微生物不能有效接触电子供受体的制约性因素,其相关反应机理还鲜有研[64]。除此之外,腐殖酸以及AQDS也可以作为电子受体进行AOM过程,SCHELLER[36]在培养ANME-2a和ANME-2c时,首次报道ANMEs可以使用腐殖酸以及AQDS作为电子受体,突破了人们对AOM电子受体范围的认识。

    • 2.1.2 ANME-2d古菌电子受体的普适性

      长期以来,研究者获得的ANME-2d富集培养物均是在以硝酸盐为电子受体状态下富集培养得到的,ANME-2d也被认为是连接淡水系统碳氮循环的关键微生物。而最近的研究表明,ANME-2d可能是一种多功能的甲烷氧化菌,在不同的环境条件下能够利用不同的电子受[39]。ANME-2d古菌拥有大量编码细胞色素C的基[33,39],研究发现其与已知的铁还原菌Ferrroglobus placidus非常相似;因此,推测ANME-2d古菌可能介导沉积物中的Fe-AOM过[65]。ETTWIG[39]向含有ANME-2d的硝酸盐富集培养体系中添加Fe(III)和Mn(IV)矿物,在没有硝酸盐存在的条件下发现ANME-2d可以介导以铁锰为电子受体的AOM,进而推测ANME-2d可以通过选择不同的电子受体以适应环境的改变。FU[66]向由ANME-2d古菌主导的N-AOM的富集培养物中添加异化铁还原菌Shewanellaoneidensis MR-1获得混合培养物,在以水铁矿作为唯一的电子受体的混合培养物中也观察到了AOM现象,据此认为是ANME-2d古菌和异化金属还原菌共同完成了Fe-AOM反应。ETTWIG[39]向含有ANME-2d古菌(40%~50%)和M. oxyfera细菌(约40%)为主导的N-AOM培养物中分别添加柠檬酸铁、水铁矿和水钠锰矿,各培养物中均检测到了Metal-AOM的活性;此外,N-AOM培养物不含其他古细菌或已知的铁还原微生物。ETTWIG[67]也做了类似的研究,向由亚硝酸盐富集培养得到的仅由M.oxyfera (约80%)组成缺少ANME-2d的富集培养物中添加铁锰电子受体,但是并没有检测到Metal-AOM活性。这些研究表明,N-AOM富集培养物中的ANME-2d古菌可以介导Metal-AOM,无论是可溶性还是不溶性金属氧化[39]。而LU[68]研究了Cr-AOM微生物化学过程,研究表明ANME-2d古菌也可能单独或者与其他微生物协同驱动Cr(VI)-AOM,这更进一步地证明了ANME-2d可能具有介导Metal-AOM的能力。蔡朝[69]还研究了H2/CH4-MBfR还原SeO42-的微生物过程,首次证实了微生物能够以CH4作为唯一的电子供体驱动SeO42-介导的AOM过程。此研究结果拓宽了CH4在废水处理中的应用前景及价值,其生物学机理有待进一步研究。

      除了可以驱动Metal-AOM以外,ANME-2d古菌还被发现可以利用硫酸盐作为电子受体驱动SAMO。SCHUBERT[70]在缺少硝酸盐和亚硝酸盐的意大利Cadagno湖沉积物中发现了SAMO现象,并且ANME-2d是唯一检测到的甲烷厌氧氧化菌。此外,来自富含低盐水的ANME-2a/b和ANME-2d的培养物中SAMO也被检测到,但在向该富集培养物中添加硝酸盐、水铁矿、腐殖酸等其他电子受体均没有检测到AOM现象,因此,ANME-2d古菌被推测能够驱动SAMO[52]

      有研[39]表明,ANME-2d可以利用不同种类多种形式的电子受体,包括硝酸盐、硫酸盐、可溶高价金属离子,不溶金属氧化物等,这说明ANME-2d可以根据环境的不同进一步选择电子受体。因此,其相关的代谢途径,在面临不同类型不同形态的电子受体时,其相关的电子转移途径,与其他协同微生物之间的关系就是突破ANME-2d作用机制的关键性问题。

    • 2.2 ANME-2d古菌的电子转移机制

    • 2.2.1 硝酸盐作为电子受体的胞内电子转移机制

      ANME-2d古菌主要有3种可能的电子转移方式如图2所示。ANME-2d古菌可以独立完成硝酸盐驱动的甲烷厌氧氧化反应,而不需要其他微生物的参与,在氧化甲烷的同时可以将硝酸盐还原为亚硝酸盐,宏基因测序也表明了ANME-2d古菌不仅具有氧化甲烷的关键基因,还具有硝酸盐还原酶的基[31]。在ANME-2d古菌中发现的逆向产甲烷途径是在ANMEs古菌中首次发现的最为完整的逆向产甲烷途径,该途径包含了所有的编码甲基辅酶-M-还原酶(Mcr)亚基的基因(mcrABCDG)和编码N5N10-亚甲基-H4MPT还原酶(Mer)的基因(mer)[69]。到目前为止,ANME-2d古菌基因组测序分析所取得的培养物均来自生物反应器。在这些反应器中,ANME-2d古菌均是和NC10门细菌同时存在的,比如厌氧氨氧化细菌(Ca. Kueneniastuttgartiensis)[45]M. oxyfera[33,42,44]。这表明ANME-2d可能依赖这些细菌去除NO2-[45]。在N-AOM中,ANME-2d除了可以介导生成NO2-,还能通过合成一种c型亚硝酸盐还原酶(NrfAH)将产生的NO2-还原为NH4+,进而解除由于NO2-浓度过高而产生的毒副作用。因此,ANME-2d古菌具备单独解除过高NO2-的能力,而不需要M. oxyfera细菌的参[69]。即ANME-2d古菌可以单独完成硝酸根驱动的甲烷厌氧氧化,而不需要其他微生物协助完成电子转移或代谢相关中间产物。

      图2
                            ANME-2d古菌的3种电子转移方式

      图2 ANME-2d古菌的3种电子转移方式

      Fig. 2 Three electron transfer methods of ANME-2d

    • 2.2.2 金属氧化物等作为可选择电子受体的胞外电子转移机制

      ANME-2d不仅可以利用硝酸盐这种可溶电子受[33],ANME-2d可以参与SAMO过[69],还可以还原难溶的金属氧化物(Fe(III)、Mn(IV))以进行甲烷氧化;但这种难溶的电子受体如何被ANME-2d古菌利用,其电子转移机制是什么,现在还存在争论,主要的电子转移途径可能存在以下几种。

      1) 胞外电子直接转移(DEET)。与环境中其他相关的电子受体不一样,Fe(III)和Mn(IV)经常以不溶固体的形式存在,因此它们不能直接被转移到细胞[71]。ETTWIG[39]发现,ANME-2d可以单独完成Metal-AOM,且通过宏基因技术在其富集培养物中发现了比地杆菌属丰度更高的编码细胞色素C的蛋白基因。这些细胞色素C被认为是地杆菌属等异化金属还原菌进行DEET反应过程必须的导电介[72,73],可以进行胞外电子的转移过程。同时通过对比实验,发现在硝酸盐富集环境中ANME-2d细胞色素C基因的表达非常低,这说明细胞色素C在Metal-AOM电子转移中起到至关重要的作[65]。因此,研究者推断ANME-2d在驱动Metal-AOM时的电子转移方式可能是像异化金属还原菌一样通过直接电子转移(DEET)来进行[71]。除此之外,研究者发现在ANME-1、ANME-2a等古菌中也发现了编码细胞色素C的基因,而这些基因的表达和金属还原之间的关系还有待证明。显然Metal-AOM的电子转移方式将比单纯异化金属还原的过程要复杂的多。有关ANME-2d在不同电子受体条件下的细胞色素C的表达仍需探[73,74]

      2) 种间电子转移机制(DIET)。ANMEs被发现时被证明是和SRB协同完成甲烷氧化和硫酸盐还原的过程,MILUCKA[53]提出以硫酸根作为电子受体的SAOM反应是由ANMEs古菌独立完成的。WANKEL[75]则证明了ANME-2古菌的分支单独完成了以硫酸盐还原的零价硫作为为中间载体的AOM全过程。对于ANME-2d这种特殊的ANMEs古菌,其与其他微生物之间的关联也一直是科学家们关注的热点问题。

      FU[66]向N-AOM的富集培养物(由ANME-2d主导)中添加异化铁还原菌Shewanellaoneidensis MR-1获得混合培养物,发现了2种微生物在培养过程中丰度均有所增加,并推测2种微生物可能是通过电子穿梭体、细胞色素蛋白载体、纳米导线等方式协同完成Metal-AOM电子转移的过程。LU[68]通过在ANME-2d富集培养物中加入Cr(VI)也发现了甲烷氧化伴随Cr(VI)还原的过程,推测可能是ANME-2d和一种未知的Cr(VI)还原微生物共同完成了Cr(VI)-AOM的过程。而其完成方式可能是通过DIET种间电子转移方式完成。相较于常规的电子转移体系,DIET由于不需要中间电子传递体作为电子载体,而直接通过微生物自身的酶或者导电鞭毛等作为介体,省去了生成中间产物时所需要的酶和能量等。由于AOM反应的活化能要远低于甲烷好氧氧化,所以DIET相较于其他电子转移方式可能更加适合ANMEs古菌与其他微生物协同完成甲烷的氧化过程。

      本研究以2种锰矿物电子受体(天然锰矿粉;人工合成δ-MnO2)和2种不同接种污泥(锰矿石人工湿地污泥;由污水厂厌氧段污泥、河流底泥以及水稻田土壤所组成的混合污泥),以甲烷作为唯一电子供体,超过700 d的富集培养,首次在富集系统中获得了4种锰矿物电子受体驱动的具有甲烷厌氧氧化效果的富集培养物。在进行以锰矿为电子受体的甲烷厌氧氧化富集培养过程中也发现了ANME-2d古菌和异化金属还原菌共存的现象,并且通过qPCR、FISH等手段发现在连续培养过程中2种微生物的绝对丰度均呈现增长的趋势。研究结果证明了锰氧化物可以耦合AOM反应,并且ANME-2d和异化金属还原菌可能共同驱动了Mn-AOM反应。

      电子可以从ANMEs微生物转移到与矿物质相关的金属离子上,反之亦然;由于微生物的细胞膜在生理上说来是不可渗透的并且矿物质也不是导电的,因此,微生物必须发展出与细胞外矿物质交换电子(如c型细胞色素和微生物纳米导线)的能力的分子机制,即胞外电子转移机[75]。关于ANME-2d的电子转移机制,根据不同的电子受体环境,可能呈现出不同的电子转移方[64]。在以硝酸盐为电子受体时,ANME-2d可以通过逆向产甲烷途径独立完成甲烷氧化和硝酸盐还原的过程,而在与其他电子受体如金属氧化物等难以进入细胞体内的电子受体,则可能要通过编码细胞色素C等胞外电子载体来进行电子转移过[39]。这也说明ANME-2d的电子转移机制可能并不是固定的,而是随着电子受体环境的改变而改变,自然环境中的电子受体多时可能需要通过与其他微生物协同完成甲烷厌氧氧化过程。

    • 3 结论与展望

      1) 淡水系统是地球重要的温室气体排放源,而作为在淡水系统中广泛存在的ANMEs古菌对于温室气体效应的减缓和碳元素循环具有重要意义。国内外学者对ANMEs介导下不同电子受体AOM反应进行了大量的研究,这些反应或由ANMEs单独完成,或与其他微生物协同完成,而其相关作用机制尚未明晰。深入研究ANMEs在淡水系统中的作用机制及相关分子生物学机理是明晰淡水系统元素循环和实现甲烷减排的关键。

      2) 目前污水处理技术面临2大主要问题:污水中碳源不足难以实现脱氮过程以及污水处理过程中衍生的大量温室气体CH4的排放。而ANMEs古菌可以同步去除甲烷、氮素和高价金属离子等且不需要额外昂贵的电子供体如乙酸和甲醇等,具有潜在的应用前景。并且有研究报道表明ANMEs可以单独或者协同其他异化金属还原菌去除重金属镉、砷高价化合物,最新研究发现ANMEs可以用于处理染料废水。

      3) ANMEs古菌倍增时间较长,生长缓慢,是否有可能应用到污水处理过程中,仍需要进一步对ANMEs相关反应机理和培养条件进行进一步研究和优化。未来的研究可以着重于缩短ANMEs的培养周期并且增强AOM反应速率,揭示ANMEs的生理特性、作用机制、电子转移途径等,以期实现低能耗、低风险的生态污水处理方式。

      4) 到目前为止,关于ANME-2d富集培养物报道的研究较少,ANME-2d的富集培养物也远远少于需要用来研究的原材料。而ANME-2d独特的电子受体选择性和电子转移机制决定其在淡水生境的重要地位。未来研究可以关注ANME-2d的工程应用价值,如与厌氧氨氧化细菌耦合同步实现氨氮和硝酸盐氮的去除,还可以用于难降解有机物处理如PPCPs等,应用前景较为广泛。

      5) 淡水生境是目前学者重点研究的对象,但目前发现的ANMEs多存在于天然生境中,而在人为影响下的大坝水库、库区消落带等也是甲烷排放潜在来源,而关于人为生境内ANMEs研究还鲜有报道。今后的研究可以关注不同人为淡水生态系统中ANMEs存在可能性及作用过程,对人为生境建成后的生态恢复提供必要的支撑。

    • 参考文献

      • 1

        CAI Y F, ZHENG Y, BODELIER P L, et al. Conventional methanotrophs are responsible for atmospheric methane oxidation in paddy soils[J]. Nature Communications, 2016, 7: 1-10.

      • 2

        SU J, HU C, YAN X, et al. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice[J]. Nature, 2015, 523(7562): 602-606.

      • 3

        RHEE T S, KETTLE A J, ANDREAE M O. Methane and nitrous oxide emissions from the ocean: A reassessment using basin-wide observations in the Atlantic[J]. Journal of Geophysical Research Atmospheres, 2009, 114: 1-20.

      • 4

        TAMAI N, TAKENAKA C, ISHIZUKA S. Water-soluble Al inhibits methane oxidation at atmospheric concentration levels in Japanese forest soil[J]. Soil Biology & Biochemistry, 2007, 39(7): 1730-1736.

      • 5

        BAROR I, ELVERT M, ECKERT W, et al. Iron-coupled anaerobic oxidation of methane performed by a mixed bacterial-archaeal community based on poorly-reactive minerals[J]. Environmental Science & Technology, 2017, 51(21): 12293-12301.

      • 6

        KNITTEL K, BOETIUS A. Anaerobic oxidation of methane: Progress with an unknown process[J]. Annual Review of Microbiology, 2008, 63: 311-334.

      • 7

        SEGARRA K E, SCHUBOTZ F, SAMARKIN V, et al. High rates of anaerobic methane oxidation in freshwater wetlands reduce potential atmospheric methane emissions[J]. Nature Communications, 2015, 6: 1-8.

      • 8

        RAGHOEBARSING A A, OL A, PASSCHOONEN K T V D, et al. A microbial consortium couples anaerobic methane oxidation to denitrification[J]. Nature, 2006, 440(7086): 918-921.

      • 9

        ISLAS-LIMA S, THALASSO F, GÓMEZ-HERNANDEZ J. Evidence of anoxic methane oxidation coupled to denitrification[J]. Water Research, 2004, 38(1): 13-16.

      • 10

        HU S, ZENG R J, BUROW L C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.

      • 11

        SHEN L D, WU H S, LIU X, et al. Cooccurrence and potential role of nitrite- and nitrate-dependent methanotrophs in freshwater marsh sediments[J]. Water Research, 2017, 123: 162-172.

      • 12

        PADILLA C C, RISTOW L A, SARODE N. NC10 bacteria in marine oxygen minimum zones[J]. ISME Journal, 2016, 10(8): 2067-2071.

      • 13

        WANG Y, HUANG P, YE F, et al. Nitrite-dependent anaerobic methane oxidizing bacteria along the water level fluctuation zone of the Three Gorges Reservoir[J]. Applied Microbiology & Biotechnology, 2016, 100(4): 1977-1986.

      • 14

        CHEN J, ZHOU Z, GU J D. Complex community of nitrite-dependent anaerobic methane oxidation bacteria in coastal sediments of the Mai Po wetland by PCR amplification of both 16S rRNA and pmoA genes[J]. Applied Microbiology & Biotechnology, 2015, 99(3): 1463-1473.

      • 15

        柴风光, 卢培利, 李微薇, 等. 利用硝酸盐和亚硝酸盐同步富集厌氧甲烷氧化微生物的比较实验[J]. 微生物学通报, 2018, 45(4): 762-770.

      • 16

        HU B L, HE Z F, GENG S, et al. Cultivation of nitrite-dependent anaerobic methane-oxidizing bacteria: Impact of reactor configuration[J]. Applied Microbiology & Biotechnology, 2014, 98(18): 7983-7991.

      • 17

        HATAMOTO M, KIMURA M, SATO T, et al. Enrichment of denitrifying methane-oxidizing microorganisms using up-flow continuous reactors and batch cultures[J]. Plos One, 2014, 9(12): 1-12.

      • 18

        ZHU B, VAN D G, FRITZ C, et al. Anaerobic oxidization of methane in a minerotrophic peatland: Enrichment of nitrite-dependent methane-oxidizing bacteria[J]. Applied & Environmental Microbiology, 2012, 78(24): 8657-8665.

      • 19

        LUESKEN F A, ALEN T A V, BIEZEN E V D, et al. Diversity and enrichment of nitrite-dependent anaerobic methane oxidizing bacteria from wastewater sludge[J]. Applied & Environmental Microbiology, 2011, 92(4): 845-854.

      • 20

        HE Z F, CAI C, SHEN L D, et al. Effect of inoculum sources on the enrichment of nitrite-dependent anaerobic methane-oxidizing bacteria[J]. Applied Microbiology & Biotechnology, 2015, 99(2): 939-946.

      • 21

        HE Z F, GENG S, PAN Y W, et al. Improvement of the trace metal composition of medium for nitrite-dependent anaerobic methane oxidation bacteria: Iron (II) and copper (II) make a difference[J]. Water Research, 2015, 85: 235-243.

      • 22

        YAN P G, LI M C, WEI G S, et al. Molecular fingerprint and dominant environmental factors of nitrite-dependent anaerobic methane-oxidizing bacteria in sediments from the Yellow River estuary, China[J]. Plos One, 2015, 10(9): 1-14.

      • 23

        HU S, ZENG R J, KELLER J, et al. Effect of nitrate and nitrite on the selection of microorganisms in the denitrifying anaerobic methane oxidation process[J]. Environmental Microbiology Reports, 2011, 3(3): 315-319.

      • 24

        MING L W, ETTWIG K F, JETTEN M S M, et al. A new intra-aerobic metabolism in the nitrite-dependent anaerobic methane-oxidizing bacterium Candidatus Methylomirabilis oxyfera[J]. Biochemical Society Transactions, 2011, 39(1): 243-248.

      • 25

        HE Z F, CAI C Y, WANG J Q, et al. A novel denitrifying methanotroph of the NC10 phylum and its microcolony[J]. Scientific Reports, 2016, 6: 1-10.

      • 26

        HE Z F, WANG J Q, HU J J, et al. Improved PCR primers to amplify 16S rRNA genes from NC10 bacteria[J]. Applied Microbiology & Biotechnology, 2016, 100(11): 5099-5108.

      • 27

        HE Z F, CAI C, GENG S, et al. Mdodeling a nitrite-dependent anaerobic methane oxidation process: Parameters identification and model evaluation[J]. Bioresource Technology, 2013, 147(8): 315-320.

      • 28

        ETTWIG K F, BUTLER M K, LE PASLIER D, et al. Nitrite-driven anaerobic methane oxidation by oxygenic bacteria[J]. Nature, 2010, 464(7288): 543-548.

      • 29

        HU S, ZENG R J, BUROW L C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.

      • 30

        ETTWIG K F, ALEN T V, PASSCHOONEN K T V D, et al. Enrichment and molecular detection of denitrifying methanotrophic bacteria of the NC10 phylum[J]. Applied Microbiology & Biotechnology, 2009, 75(11): 3656-3662.

      • 31

        TIMMERS P H A, WIDJAJA-GREEFKES H C A, PLUGGE C M, et al. Evaluation and optimization of PCR primers for selective and quantitative detection of marine ANME subclusters involved in sulfate-dependent anaerobic methane oxidation[J]. Applied Microbiology & Biotechnology, 2017, 14: 1-13.

      • 32

        HINRICHS K U, HAYES J M, SYLVA S P, et al. Methane-consuming archaebacteria in marine sediments[J]. Nature, 1999, 398(6730): 802-805.

      • 33

        HAROON M F, SHIHU H, YING S, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.

      • 34

        TIMMERS P H A, WELTE C U, KOEHORST J J, et al. Reverse methanogenesis and respiration in methanotrophic archaea[J]. Archaea, 2017, 17: 1-22.

      • 35

        周京勇, 刘冬秀, 何池全, 等. 土壤中甲烷厌氧氧化菌多样性的分子检测[J]. 生态学报, 2015, 35(11): 3491-3503.

      • 36

        SCHELLER S, YU H, CHADWICK G L, et al. Artificial electron acceptors decouple archaeal methane oxidation from sulfate reduction[J]. Science, 2016, 351(6274): 703-707.

      • 37

        陈颖. 厌氧甲烷氧化微生物代谢分子机制及其潜在参与矿物形成机理的研究[D]. 上海: 上海交通大学, 2014.

      • 38

        FU L, DING Z W, DING J, et al. The role of paraffin oil on the interaction between denitrifying anaerobic methane oxidation and Anammox processes[J]. Applied Microbiology & Biotechnology, 2015, 99(19): 7925-7936.

      • 39

        ETTWIG K F, ZHU B, SPETH D, et al. Archaea catalyze iron-dependent anaerobic oxidation of methane[J]. Proceedings of the National Academy of Sciences ,2016, 113(45): 12792-12796.

      • 40

        DING L J, SU J Q, XU H J, et al. Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing[J]. ISME Journal, 2015, 9(3): 721-734.

      • 41

        VAKSMAA A, LÜKE C, ALEN T V, et al. Distribution and activity of the anaerobic methanotrophic community in a nitrogen-fertilized Italian paddy soil[J]. FEMS Microbiology Ecology, 2016, 92(12): 1-11.

      • 42

        SEIFERT R, NAUHAUS K, BLUMENBERG M, et al. Methane dynamics in a microbial community of the Black Sea traced by stable carbon isotopes in vitro[J]. Organic Geochemistry, 2006, 37(10): 1411-1419.

      • 43

        DING Z W, DING J, FU L, et al. Simultaneous enrichment of denitrifying methanotrophs and anammox bacteria[J]. Applied Microbiology & Biotechnology, 2014, 98(24): 10211-10221.

      • 44

        HE Z F, GENG S, SHEN L D, et al. The short- and long-term effects of environmental conditions on anaerobic methane oxidation coupled to nitrite reduction[J]. Water Research, 2015, 68(47): 554-562.

      • 45

        HAROON M F, HU S, SHI Y, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.

      • 46

        WEBER H S, HABICHT K S, THAMDRUP B. Anaerobic methanotrophic archaea of the ANME-2d cluster are active in a low-sulfate, iron-rich freshwater sediment[J]. Frontiers in Microbiology, 2017, 8: 1-13.

      • 47

        VAKSMAA A, JETTEN M S M, ETTWIG K F, et al. McrA primers for the detection and quantification of the anaerobic archaeal methanotroph Candidatus Methanoperedens nitroreducens[J]. Applied Microbiology & Biotechnology, 2017, 101(4): 1631-1641.

      • 48

        DING J, LU Y Z, FU L, et al. Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell[J]. Water Research, 2016, 110: 112-119.

      • 49

        VAKSMAA A, GUERRERO-CRUZ S, ALEN T A V, et al. Enrichment of anaerobic nitrate-dependent methanotrophic Candidatus Methanoperedens nitroreducens archaea from an Italian paddy field soil[J]. Applied Microbiology & Biotechnology, 2017, 101(18): 7075-7084.

      • 50

        AI M, MOCHIMARU H, KAZAMA H, et al. Development of 16S rRNA gene-targeted primers for detection of archaeal anaerobic methanotrophs (ANMEs)[J]. FEMS Microbiology Letters, 2010, 297(1): 31-37.

      • 51

        STROUS M, JETTEN M S M. Anaerobic oxidation of methane and ammonium[J]. Annual Review of Microbiology, 2004, 58(1): 99-117.

      • 52

        TIMMERS P H, SUAREZZULUAGA D A, ROSSEM M V, et al. Anaerobic oxidation of methane associated with sulfate reduction in a natural freshwater gas source[J]. ISME Journal, 2016, 10(6): 1400-1412.

      • 53

        MILUCKA J, FERDELMAN T G, POLERECKY L, et al. Zero-valent sulphur is a key intermediate in marine methane oxidation[J]. Nature, 2012, 491(7425): 541-546.

      • 54

        WICKLAND K, HAMDAN L, ROOZE J, et al. Iron‐dependent anaerobic oxidation of methane in coastal surface sediments: Potential controls and impact[J]. Limnology & Oceanography, 2016, 61: S267-S282.

      • 55

        EGGER M, RASIGRAF O, SAPART C J, et al. Iron-mediated anaerobic oxidation of methane in brackish coastal sediments[J]. Environmental Science & Technology, 2015, 49(1): 277-283.

      • 56

        HANSEL C M, LENTINI C J, TANG Y, et al. Dominance of sulfur-fueled iron oxide reduction in low-sulfate freshwater sediments[J]. ISME Journal, 2015, 9(11): 2400-2412.

      • 57

        RIEDINGER N, FORMOLO M J, LYONS T W, et al. An inorganic geochemical argument for coupled anaerobic oxidation of methane and iron reduction in marine sediments[J]. Geobiology, 2014, 12(2): 172-181.

      • 58

        TORRES N T, OCH L M, HAUSER P C, et al. Early diagenetic processes generate iron and manganese oxide layers in the sediments of Lake Baikal, Siberia[J]. Environmental Science Processes & Impacts, 2014, 16(4): 879-889.

      • 59

        NORDI K Á, BO T, SCHUBERT C J. Anaerobic oxidation of methane in an iron-rich Danish freshwater lake sediment[J]. Limnology & Oceanography, 2013, 58(2): 546-554.

      • 60

        AMOS R T, BEKINS B A, COZZARELLI I M, et al. Evidence for iron-mediated anaerobic methane oxidation in a crude oil-contaminated aquifer[J]. Geobiology, 2012, 10(6): 506-517.

      • 61

        HOLMKVIST L, FERDELMAN T G, BO B J. A cryptic sulfur cycle driven by iron in the methane zone of marine sediment (Aarhus Bay, Denmark) [J]. Geochimica Et Cosmochimica Acta, 2011, 75(12): 3581-3599.

      • 62

        SIVAN O, ADLER M, PEARSON A, et al. Geochemical evidence for iron‐mediated anaerobic oxidation of methane[J]. Limnology & Oceanography, 2011, 56(4): 1536-1544.

      • 63

        BEAL E J, HOUSE C H, ORPHAN V J. Manganese- and iron-dependent marine methane oxidation[J]. Science, 2009, 325(5937): 184-187.

      • 64

        HE Z F, ZHANG Q Y, FENG Y D, et al. Microbiological and environmental significance of metal-dependent anaerobic oxidation of methane[J]. Science of the Total Environment, 2017, 610-611: 759-768.

      • 65

        Arslan A, Speth D R, De G R M, et al. A metagenomics-based metabolic model of nitrate-dependent anaerobic oxidation of methane by Methanoperedens-like archaea[J]. Frontiers in Microbiology, 2015, 6: 1-14.

      • 66

        FU L, LI S W, DING Z W, et al. Iron reduction in the DAMO/Shewanellaoneidensis MR-1 coculture system and the fate of Fe(II)[J]. Water Research, 2016, 88: 808-815.

      • 67

        ETTWIG K F, SHIMA S, VAN P S, et al. Denitrifying bacteria anaerobically oxidize methane in the absence of archaea[J]. Environmental Microbiology, 2010, 10(11): 3164-3173.

      • 68

        LU Y Z, FU L, DING J, et al. Cr (VI) reduction coupled with anaerobic oxidation of methane in a laboratory reactor[J]. Water Research, 2016, 102: 445-452.

      • 69

        蔡朝阳. 潮间带古菌介导的甲烷厌氧氧化过程研究[D]. 杭州: 浙江大学, 2017.

      • 70

        SCHUBERT C J, FRANCISCO V, TINA L S B, et al. Evidence for anaerobic oxidation of methane in sediments of a freshwater system (Lago di Cadagno) [J]. FEMS Microbiology Ecology, 2015, 76(1): 26-38.

      • 71

        ONI O E, FRIEDRICH M W. Metal oxide reduction linked to anaerobic methane oxidation[J]. Trends in Microbiology, 2017, 25(2): 88-90.

      • 72

        WANG F, ZHANG Y, CHEN Y, et al. Methanotrophic archaea possessing diverging methane-oxidizing and electron-transporting pathways[J]. ISME Journal, 2014, 8(5): 1069-1078.

      • 73

        SHI L, SQUIER T C, ZACHARA J M, et al. Respiration of metal (hydr)oxides by shewanella and geobacter: A key role for multihaem c-type cytochromes[J]. Molecular Microbiology, 2010, 65(1): 12-20.

      • 74

        SHI L, DONG H L, REGUERA G, et al. Extracellular electron transfer mechanisms between microorganisms and minerals[J]. Nature Reviews Microbiology, 2016, 14(10): 651-662.

      • 75

        WANKEL S D, ADAMS M, JOHNSTON D T, et al. Anaerobic methane oxidation in metalliferous hydrothermal sediments: Influence on carbon flux and decoupling from sulfate reduction[J]. Environmental Microbiology, 2012, 14(10): 2726-2740.

  • [1] CAI Y F, ZHENG Y, BODELIER P L, et al. Conventional methanotrophs are responsible for atmospheric methane oxidation in paddy soils[J]. Nature Communications, 2016, 7: 1-10.
    [2] SU J, HU C, YAN X, et al. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice[J]. Nature, 2015, 523(7562): 602-606.
    [3] RHEE T S, KETTLE A J, ANDREAE M O. Methane and nitrous oxide emissions from the ocean: A reassessment using basin-wide observations in the Atlantic[J]. Journal of Geophysical Research Atmospheres, 2009, 114: 1-20.
    [4] TAMAI N, TAKENAKA C, ISHIZUKA S. Water-soluble Al inhibits methane oxidation at atmospheric concentration levels in Japanese forest soil[J]. Soil Biology & Biochemistry, 2007, 39(7): 1730-1736.
    [5] BAROR I, ELVERT M, ECKERT W, et al. Iron-coupled anaerobic oxidation of methane performed by a mixed bacterial-archaeal community based on poorly-reactive minerals[J]. Environmental Science & Technology, 2017, 51(21): 12293-12301.
    [6] KNITTEL K, BOETIUS A. Anaerobic oxidation of methane: Progress with an unknown process[J]. Annual Review of Microbiology, 2008, 63: 311-334.
    [7] SEGARRA K E, SCHUBOTZ F, SAMARKIN V, et al. High rates of anaerobic methane oxidation in freshwater wetlands reduce potential atmospheric methane emissions[J]. Nature Communications, 2015, 6: 1-8.
    [8] RAGHOEBARSING A A, OL A, PASSCHOONEN K T V D, et al. A microbial consortium couples anaerobic methane oxidation to denitrification[J]. Nature, 2006, 440(7086): 918-921.
    [9] ISLAS-LIMA S, THALASSO F, GóMEZ-HERNANDEZ J. Evidence of anoxic methane oxidation coupled to denitrification[J]. Water Research, 2004, 38(1): 13-16.
    [10] HU S, ZENG R J, BUROW L C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.
    [11] SHEN L D, WU H S, LIU X, et al. Cooccurrence and potential role of nitrite- and nitrate-dependent methanotrophs in freshwater marsh sediments[J]. Water Research, 2017, 123: 162-172.
    [12] PADILLA C C, RISTOW L A, SARODE N. NC10 bacteria in marine oxygen minimum zones[J]. ISME Journal, 2016, 10(8): 2067-2071.
    [13] WANG Y, HUANG P, YE F, et al. Nitrite-dependent anaerobic methane oxidizing bacteria along the water level fluctuation zone of the Three Gorges Reservoir[J]. Applied Microbiology & Biotechnology, 2016, 100(4): 1977-1986.
    [14] CHEN J, ZHOU Z, GU J D. Complex community of nitrite-dependent anaerobic methane oxidation bacteria in coastal sediments of the Mai Po wetland by PCR amplification of both 16S rRNA and pmoA genes[J]. Applied Microbiology & Biotechnology, 2015, 99(3): 1463-1473.
    [15] 柴风光, 卢培利, 李微薇, 等. 利用硝酸盐和亚硝酸盐同步富集厌氧甲烷氧化微生物的比较实验[J]. 微生物学通报, 2018, 45(4): 762-770.
    [16] HU B L, HE Z F, GENG S, et al. Cultivation of nitrite-dependent anaerobic methane-oxidizing bacteria: Impact of reactor configuration[J]. Applied Microbiology & Biotechnology, 2014, 98(18): 7983-7991.
    [17] HATAMOTO M, KIMURA M, SATO T, et al. Enrichment of denitrifying methane-oxidizing microorganisms using up-flow continuous reactors and batch cultures[J]. Plos One, 2014, 9(12): 1-12.
    [18] ZHU B, VAN D G, FRITZ C, et al. Anaerobic oxidization of methane in a minerotrophic peatland: Enrichment of nitrite-dependent methane-oxidizing bacteria[J]. Applied & Environmental Microbiology, 2012, 78(24): 8657-8665.
    [19] LUESKEN F A, ALEN T A V, BIEZEN E V D, et al. Diversity and enrichment of nitrite-dependent anaerobic methane oxidizing bacteria from wastewater sludge[J]. Applied & Environmental Microbiology, 2011, 92(4): 845-854.
    [20] HE Z F, CAI C, SHEN L D, et al. Effect of inoculum sources on the enrichment of nitrite-dependent anaerobic methane-oxidizing bacteria[J]. Applied Microbiology & Biotechnology, 2015, 99(2): 939-946.
    [21] HE Z F, GENG S, PAN Y W, et al. Improvement of the trace metal composition of medium for nitrite-dependent anaerobic methane oxidation bacteria: Iron (II) and copper (II) make a difference[J]. Water Research, 2015, 85: 235-243.
    [22] YAN P G, LI M C, WEI G S, et al. Molecular fingerprint and dominant environmental factors of nitrite-dependent anaerobic methane-oxidizing bacteria in sediments from the Yellow River estuary, China[J]. Plos One, 2015, 10(9): 1-14.
    [23] HU S, ZENG R J, KELLER J, et al. Effect of nitrate and nitrite on the selection of microorganisms in the denitrifying anaerobic methane oxidation process[J]. Environmental Microbiology Reports, 2011, 3(3): 315-319.
    [24] MING L W, ETTWIG K F, JETTEN M S M, et al. A new intra-aerobic metabolism in the nitrite-dependent anaerobic methane-oxidizing bacterium Candidatus Methylomirabilis oxyfera[J]. Biochemical Society Transactions, 2011, 39(1): 243-248.
    [25] HE Z F, CAI C Y, WANG J Q, et al. A novel denitrifying methanotroph of the NC10 phylum and its microcolony[J]. Scientific Reports, 2016, 6: 1-10.
    [26] HE Z F, WANG J Q, HU J J, et al. Improved PCR primers to amplify 16S rRNA genes from NC10 bacteria[J]. Applied Microbiology & Biotechnology, 2016, 100(11): 5099-5108.
    [27] HE Z F, CAI C, GENG S, et al. Mdodeling a nitrite-dependent anaerobic methane oxidation process: Parameters identification and model evaluation[J]. Bioresource Technology, 2013, 147(8): 315-320.
    [28] ETTWIG K F, BUTLER M K, LE PASLIER D, et al. Nitrite-driven anaerobic methane oxidation by oxygenic bacteria[J]. Nature, 2010, 464(7288): 543-548.
    [29] HU S, ZENG R J, BUROW L C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.
    [30] ETTWIG K F, ALEN T V, PASSCHOONEN K T V D, et al. Enrichment and molecular detection of denitrifying methanotrophic bacteria of the NC10 phylum[J]. Applied Microbiology & Biotechnology, 2009, 75(11): 3656-3662.
    [31] TIMMERS P H A, WIDJAJA-GREEFKES H C A, PLUGGE C M, et al. Evaluation and optimization of PCR primers for selective and quantitative detection of marine ANME subclusters involved in sulfate-dependent anaerobic methane oxidation[J]. Applied Microbiology & Biotechnology, 2017, 14: 1-13.
    [32] HINRICHS K U, HAYES J M, SYLVA S P, et al. Methane-consuming archaebacteria in marine sediments[J]. Nature, 1999, 398(6730): 802-805.
    [33] HAROON M F, SHIHU H, YING S, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.
    [34] TIMMERS P H A, WELTE C U, KOEHORST J J, et al. Reverse methanogenesis and respiration in methanotrophic archaea[J]. Archaea, 2017, 17: 1-22.
    [35] 周京勇, 刘冬秀, 何池全, 等. 土壤中甲烷厌氧氧化菌多样性的分子检测[J]. 生态学报, 2015, 35(11): 3491-3503.
    [36] SCHELLER S, YU H, CHADWICK G L, et al. Artificial electron acceptors decouple archaeal methane oxidation from sulfate reduction[J]. Science, 2016, 351(6274): 703-707.
    [37] 陈颖. 厌氧甲烷氧化微生物代谢分子机制及其潜在参与矿物形成机理的研究[D]. 上海: 上海交通大学, 2014.
    [38] FU L, DING Z W, DING J, et al. The role of paraffin oil on the interaction between denitrifying anaerobic methane oxidation and Anammox processes[J]. Applied Microbiology & Biotechnology, 2015, 99(19): 7925-7936.
    [39] ETTWIG K F, ZHU B, SPETH D, et al. Archaea catalyze iron-dependent anaerobic oxidation of methane[J]. Proceedings of the National Academy of Sciences ,2016, 113(45): 12792-12796.
    [40] DING L J, SU J Q, XU H J, et al. Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing[J]. ISME Journal, 2015, 9(3): 721-734.
    [41] VAKSMAA A, LüKE C, ALEN T V, et al. Distribution and activity of the anaerobic methanotrophic community in a nitrogen-fertilized Italian paddy soil[J]. FEMS Microbiology Ecology, 2016, 92(12): 1-11.
    [42] SEIFERT R, NAUHAUS K, BLUMENBERG M, et al. Methane dynamics in a microbial community of the Black Sea traced by stable carbon isotopes in vitro[J]. Organic Geochemistry, 2006, 37(10): 1411-1419.
    [43] DING Z W, DING J, FU L, et al. Simultaneous enrichment of denitrifying methanotrophs and anammox bacteria[J]. Applied Microbiology & Biotechnology, 2014, 98(24): 10211-10221.
    [44] HE Z F, GENG S, SHEN L D, et al. The short- and long-term effects of environmental conditions on anaerobic methane oxidation coupled to nitrite reduction[J]. Water Research, 2015, 68(47): 554-562.
    [45] HAROON M F, HU S, SHI Y, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.
    [46] WEBER H S, HABICHT K S, THAMDRUP B. Anaerobic methanotrophic archaea of the ANME-2d cluster are active in a low-sulfate, iron-rich freshwater sediment[J]. Frontiers in Microbiology, 2017, 8: 1-13.
    [47] VAKSMAA A, JETTEN M S M, ETTWIG K F, et al. McrA primers for the detection and quantification of the anaerobic archaeal methanotroph Candidatus Methanoperedens nitroreducens[J]. Applied Microbiology & Biotechnology, 2017, 101(4): 1631-1641.
    [48] DING J, LU Y Z, FU L, et al. Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell[J]. Water Research, 2016, 110: 112-119.
    [49] VAKSMAA A, GUERRERO-CRUZ S, ALEN T A V, et al. Enrichment of anaerobic nitrate-dependent methanotrophic Candidatus Methanoperedens nitroreducens archaea from an Italian paddy field soil[J]. Applied Microbiology & Biotechnology, 2017, 101(18): 7075-7084.
    [50] AI M, MOCHIMARU H, KAZAMA H, et al. Development of 16S rRNA gene-targeted primers for detection of archaeal anaerobic methanotrophs (ANMEs)[J]. FEMS Microbiology Letters, 2010, 297(1): 31-37.
    [51] STROUS M, JETTEN M S M. Anaerobic oxidation of methane and ammonium[J]. Annual Review of Microbiology, 2004, 58(1): 99-117.
    [52] TIMMERS P H, SUAREZZULUAGA D A, ROSSEM M V, et al. Anaerobic oxidation of methane associated with sulfate reduction in a natural freshwater gas source[J]. ISME Journal, 2016, 10(6): 1400-1412.
    [53] MILUCKA J, FERDELMAN T G, POLERECKY L, et al. Zero-valent sulphur is a key intermediate in marine methane oxidation[J]. Nature, 2012, 491(7425): 541-546.
    [54] WICKLAND K, HAMDAN L, ROOZE J, et al. Iron‐dependent anaerobic oxidation of methane in coastal surface sediments: Potential controls and impact[J]. Limnology & Oceanography, 2016, 61: S267-S282.
    [55] EGGER M, RASIGRAF O, SAPART C J, et al. Iron-mediated anaerobic oxidation of methane in brackish coastal sediments[J]. Environmental Science & Technology, 2015, 49(1): 277-283.
    [56] HANSEL C M, LENTINI C J, TANG Y, et al. Dominance of sulfur-fueled iron oxide reduction in low-sulfate freshwater sediments[J]. ISME Journal, 2015, 9(11): 2400-2412.
    [57] RIEDINGER N, FORMOLO M J, LYONS T W, et al. An inorganic geochemical argument for coupled anaerobic oxidation of methane and iron reduction in marine sediments[J]. Geobiology, 2014, 12(2): 172-181.
    [58] TORRES N T, OCH L M, HAUSER P C, et al. Early diagenetic processes generate iron and manganese oxide layers in the sediments of Lake Baikal, Siberia[J]. Environmental Science Processes & Impacts, 2014, 16(4): 879-889.
    [59] K á NORDI, BO T, SCHUBERT C J. Anaerobic oxidation of methane in an iron-rich Danish freshwater lake sediment[J]. Limnology & Oceanography, 2013, 58(2): 546-554.
    [60] AMOS R T, BEKINS B A, COZZARELLI I M, et al. Evidence for iron-mediated anaerobic methane oxidation in a crude oil-contaminated aquifer[J]. Geobiology, 2012, 10(6): 506-517.
    [61] HOLMKVIST L, FERDELMAN T G, BO B J. A cryptic sulfur cycle driven by iron in the methane zone of marine sediment (Aarhus Bay, Denmark) [J]. Geochimica Et Cosmochimica Acta, 2011, 75(12): 3581-3599.
    [62] SIVAN O, ADLER M, PEARSON A, et al. Geochemical evidence for iron‐mediated anaerobic oxidation of methane[J]. Limnology & Oceanography, 2011, 56(4): 1536-1544.
    [63] BEAL E J, HOUSE C H, ORPHAN V J. Manganese- and iron-dependent marine methane oxidation[J]. Science, 2009, 325(5937): 184-187.
    [64] HE Z F, ZHANG Q Y, FENG Y D, et al. Microbiological and environmental significance of metal-dependent anaerobic oxidation of methane[J]. Science of the Total Environment, 2017, 610-611: 759-768.
    [65] Arslan A, Speth D R, De G R M, et al. A metagenomics-based metabolic model of nitrate-dependent anaerobic oxidation of methane by Methanoperedens-like archaea[J]. Frontiers in Microbiology, 2015, 6: 1-14.
    [66] FU L, LI S W, DING Z W, et al. Iron reduction in the DAMO/Shewanellaoneidensis MR-1 coculture system and the fate of Fe(II)[J]. Water Research, 2016, 88: 808-815.
    [67] ETTWIG K F, SHIMA S, VAN P S, et al. Denitrifying bacteria anaerobically oxidize methane in the absence of archaea[J]. Environmental Microbiology, 2010, 10(11): 3164-3173.
    [68] LU Y Z, FU L, DING J, et al. Cr (VI) reduction coupled with anaerobic oxidation of methane in a laboratory reactor[J]. Water Research, 2016, 102: 445-452.
    [69] 蔡朝阳. 潮间带古菌介导的甲烷厌氧氧化过程研究[D]. 杭州: 浙江大学, 2017.
    [70] SCHUBERT C J, FRANCISCO V, TINA L S B, et al. Evidence for anaerobic oxidation of methane in sediments of a freshwater system (Lago di Cadagno) [J]. FEMS Microbiology Ecology, 2015, 76(1): 26-38.
    [71] ONI O E, FRIEDRICH M W. Metal oxide reduction linked to anaerobic methane oxidation[J]. Trends in Microbiology, 2017, 25(2): 88-90.
    [72] WANG F, ZHANG Y, CHEN Y, et al. Methanotrophic archaea possessing diverging methane-oxidizing and electron-transporting pathways[J]. ISME Journal, 2014, 8(5): 1069-1078.
    [73] SHI L, SQUIER T C, ZACHARA J M, et al. Respiration of metal (hydr)oxides by shewanella and geobacter: A key role for multihaem c-type cytochromes[J]. Molecular Microbiology, 2010, 65(1): 12-20.
    [74] SHI L, DONG H L, REGUERA G, et al. Extracellular electron transfer mechanisms between microorganisms and minerals[J]. Nature Reviews Microbiology, 2016, 14(10): 651-662.
    [75] WANKEL S D, ADAMS M, JOHNSTON D T, et al. Anaerobic methane oxidation in metalliferous hydrothermal sediments: Influence on carbon flux and decoupling from sulfate reduction[J]. Environmental Microbiology, 2012, 14(10): 2726-2740.
  • 期刊类型引用(8)

    1. 刘治银,张玉兰,康世昌,付佳星,高坛光. 北极地区热融湖塘甲烷排放特征及影响因素. 冰川冻土. 2024(02): 457-474 . 百度学术
    2. 余子洁,申思,郭大陆,李致同,罗红燕. 不同类型冬水田土壤中厌氧甲烷氧化古菌的垂直分布. 江西农业大学学报. 2023(01): 220-230 . 百度学术
    3. 何盼,张超,刘嘉欣,白晋龙,卢静,侯彬. 双阳极室甲烷微生物燃料电池同步脱氮除硫性能及微生物群落分析. 微生物学通报. 2023(03): 1010-1022 . 百度学术
    4. 秦永丽,孙晓杰,王春莲,伍贝贝,薛晨楠,张红霞. 生物炭填埋场土壤覆盖层的甲烷减排性能和生物特征. 中国环境科学. 2021(01): 254-262 . 百度学术
    5. 薛怡亭,安法财,石天晶,党岩,孙德智. 反硝化型厌氧甲烷氧化微生物的富集与影响因素分析. 环境工程学报. 2021(02): 599-608 . 本站查看
    6. 闫召伟,杨菲宇,高兴祖,陈杰,李施雨,李国学,罗文海. 含硫添加剂对猪粪堆肥过程甲烷与臭气排放的影响. 农业环境科学学报. 2021(11): 2448-2455 . 百度学术
    7. 陈悦,罗明没,毛娇艳,李玮,胡斌. 反硝化型甲烷厌氧氧化作用研究进展. 应用与环境生物学报. 2021(06): 1686-1693 . 百度学术
    8. 姜怡如,高峥,李明聪. 水生生态系统中金属依赖型甲烷厌氧氧化过程的研究进展. 微生物学通报. 2020(10): 3318-3328 . 百度学术

    其他类型引用(10)

  • 加载中
    Created with Highcharts 5.0.7访问量Chart context menu近一年内文章摘要浏览量、全文浏览量、PDF下载量统计信息摘要浏览量全文浏览量PDF下载量2024-032024-042024-052024-062024-072024-082024-092024-102024-112024-122025-012025-020Highcharts.com
    Created with Highcharts 5.0.7Chart context menu访问类别分布DOWNLOAD: 20.7 %DOWNLOAD: 20.7 %FULLTEXT: 61.5 %FULLTEXT: 61.5 %META: 17.7 %META: 17.7 %DOWNLOADFULLTEXTMETAHighcharts.com
    Created with Highcharts 5.0.7Chart context menu访问地区分布其他: 69.0 %其他: 69.0 %Anshan: 0.1 %Anshan: 0.1 %Ashburn: 5.1 %Ashburn: 5.1 %Beijing: 8.3 %Beijing: 8.3 %Brooklyn: 0.1 %Brooklyn: 0.1 %Chang'an: 0.1 %Chang'an: 0.1 %Changsha: 0.4 %Changsha: 0.4 %Chengdu: 0.5 %Chengdu: 0.5 %Chongqing: 0.9 %Chongqing: 0.9 %Dongguan: 0.1 %Dongguan: 0.1 %Ewirgol: 0.1 %Ewirgol: 0.1 %Fangshan: 0.1 %Fangshan: 0.1 %Fangyuan: 0.1 %Fangyuan: 0.1 %Fuzhou: 0.1 %Fuzhou: 0.1 %Ganzhou: 0.1 %Ganzhou: 0.1 %Hangzhou: 0.4 %Hangzhou: 0.4 %Hefei: 0.1 %Hefei: 0.1 %Helixi: 0.1 %Helixi: 0.1 %Hotan: 0.1 %Hotan: 0.1 %Jinan: 0.1 %Jinan: 0.1 %Jinrongjie: 0.4 %Jinrongjie: 0.4 %Kunming: 0.1 %Kunming: 0.1 %Lanzhou: 0.1 %Lanzhou: 0.1 %luohe shi: 0.1 %luohe shi: 0.1 %Nanjing: 0.3 %Nanjing: 0.3 %Nanning: 0.1 %Nanning: 0.1 %Newark: 0.5 %Newark: 0.5 %Ningbo: 0.1 %Ningbo: 0.1 %Qingdao: 0.4 %Qingdao: 0.4 %Rongcheng: 0.1 %Rongcheng: 0.1 %Shanghai: 1.4 %Shanghai: 1.4 %Shenyang: 0.1 %Shenyang: 0.1 %Shijiazhuang: 0.3 %Shijiazhuang: 0.3 %Sujiatun: 0.1 %Sujiatun: 0.1 %Suzhou: 0.4 %Suzhou: 0.4 %Syracuse: 0.1 %Syracuse: 0.1 %Taiyuan: 0.1 %Taiyuan: 0.1 %Tel Aviv: 0.4 %Tel Aviv: 0.4 %Tianjin Municipality: 0.1 %Tianjin Municipality: 0.1 %Wenzhou: 0.1 %Wenzhou: 0.1 %Wuhan: 0.1 %Wuhan: 0.1 %Wulipu: 0.1 %Wulipu: 0.1 %Wuxi: 0.1 %Wuxi: 0.1 %Xilin Gol Meng: 0.1 %Xilin Gol Meng: 0.1 %Xingfeng: 0.1 %Xingfeng: 0.1 %Xuzhou: 0.1 %Xuzhou: 0.1 %XX: 3.5 %XX: 3.5 %Yinchuan: 0.1 %Yinchuan: 0.1 %Yulin: 0.1 %Yulin: 0.1 %Yuxi: 0.1 %Yuxi: 0.1 %Yuzhong Chengguanzhen: 0.1 %Yuzhong Chengguanzhen: 0.1 %Zhengzhou: 0.1 %Zhengzhou: 0.1 %Zhuhai: 0.1 %Zhuhai: 0.1 %上海: 0.1 %上海: 0.1 %佛山: 0.1 %佛山: 0.1 %北京: 1.0 %北京: 1.0 %南京: 0.1 %南京: 0.1 %彰化县: 0.1 %彰化县: 0.1 %武汉: 0.3 %武汉: 0.3 %深圳: 0.4 %深圳: 0.4 %衡阳: 0.1 %衡阳: 0.1 %西安: 0.1 %西安: 0.1 %郑州: 0.3 %郑州: 0.3 %重庆: 0.1 %重庆: 0.1 %其他AnshanAshburnBeijingBrooklynChang'anChangshaChengduChongqingDongguanEwirgolFangshanFangyuanFuzhouGanzhouHangzhouHefeiHelixiHotanJinanJinrongjieKunmingLanzhouluohe shiNanjingNanningNewarkNingboQingdaoRongchengShanghaiShenyangShijiazhuangSujiatunSuzhouSyracuseTaiyuanTel AvivTianjin MunicipalityWenzhouWuhanWulipuWuxiXilin Gol MengXingfengXuzhouXXYinchuanYulinYuxiYuzhong ChengguanzhenZhengzhouZhuhai上海佛山北京南京彰化县武汉深圳衡阳西安郑州重庆Highcharts.com
计量
  • 文章访问数:  8381
  • HTML全文浏览数:  8275
  • PDF下载数:  268
  • 施引文献:  18
出版历程
  • 刊出日期:  2019-06-03
翟俊, 李媛媛, 何孟狄, 马宏璞, 戴元贵. 淡水系统中甲烷厌氧氧化古菌的研究进展[J]. 环境工程学报, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098
引用本文: 翟俊, 李媛媛, 何孟狄, 马宏璞, 戴元贵. 淡水系统中甲烷厌氧氧化古菌的研究进展[J]. 环境工程学报, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098
ZHAI Jun, LI Yuanyuan, HE Mengdi, MA Hongpu, DAI Yuangui. Review on the research progress of archaeal anaerobic methanotrophs in freshwater system[J]. Chinese Journal of Environmental Engineering, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098
Citation: ZHAI Jun, LI Yuanyuan, HE Mengdi, MA Hongpu, DAI Yuangui. Review on the research progress of archaeal anaerobic methanotrophs in freshwater system[J]. Chinese Journal of Environmental Engineering, 2019, 13(5): 1009-1020. doi: 10.12030/j.cjee.201812098

淡水系统中甲烷厌氧氧化古菌的研究进展

  • 1. 重庆大学,三峡库区生态环境教育部重点实验室,重庆 400045
  • 2. 中国市政工程西南设计研究总院有限公司,成都 610081
基金项目:

国家自然科学基金资助项目51478062, 51878093国家自然科学基金资助项目(51478062, 51878093)

摘要: 甲烷厌氧氧化古菌(ANMEs)是甲烷厌氧氧化过程中的重要微生物种群,对自然生境甲烷削减的意义重大,目前研究多集中在海洋系统,而关于ANMEs古菌在淡水系统的研究较少,其相关作用机理和工程应用的研究也尚处于初步阶段。在综合文献及前期研究基础上,介绍了ANMEs为主线的淡水系统甲烷厌氧氧化机制,分析了ANMEs的微生物学特性及地理分布,系统梳理了ANME-2d古菌针对不同电子受体(NO3-、Fe3+、Cr6+等)的电子转移体系研究进展;指出了ANME-2d及其他ANMEs可能根据环境改变而选择不同的电子受体,其相对应的电子转移机制也不同。通过对不同电子受体下的ANME-2d及其他ANMEs在淡水系统中的作用机制进行讨论分析,可为淡水系统甲烷厌氧氧化机制和碳循环过程提供理论依据,并为在工程中应用ANMEs实现同步污染物处理和甲烷削减提供新的思路。

English Abstract

      摘要

      甲烷厌氧氧化古菌(ANMEs)是甲烷厌氧氧化过程中的重要微生物种群,对自然生境甲烷削减的意义重大,目前研究多集中在海洋系统,而关于ANMEs古菌在淡水系统的研究较少,其相关作用机理和工程应用的研究也尚处于初步阶段。在综合文献及前期研究基础上,介绍了ANMEs为主线的淡水系统甲烷厌氧氧化机制,分析了ANMEs的微生物学特性及地理分布,系统梳理了ANME-2d古菌针对不同电子受体(NO3-、Fe3+、Cr6+等)的电子转移体系研究进展;指出了ANME-2d及其他ANMEs可能根据环境改变而选择不同的电子受体,其相对应的电子转移机制也不同。通过对不同电子受体下的ANME-2d及其他ANMEs在淡水系统中的作用机制进行讨论分析,可为淡水系统甲烷厌氧氧化机制和碳循环过程提供理论依据,并为在工程中应用ANMEs实现同步污染物处理和甲烷削减提供新的思路。

      Abstract

      Archaeal anaerobic methanotrophs (ANMEs) are key microorganisms in the anaerobic oxidation of methane (AOM), which is of great significance in methane reduction of natural environment. The current researches mainly focused on the ocean systems, while there is little known on the ANMEs are in the freshwater systems. The studies on mechanisms and applications of AOM in the freshwater systems are also rare. On the basis of previous literatures and studies review, the mechanisms of ANME-mediated AOM in the freshwater systems were introduced, the microbial characteristics and geographic distribution were analyzed, and the progress of studies on electron transfer when ANME-2d using different electron acceptors (NO3-, Fe3+, Cr6+, etc.) was systematically reviewed. The ANME-2d, as well as other ANMEs, could select different electron acceptors depending on environment variations which were assigned to different electron-transferring mechanisms. The discussion on the mechanisms of ANME-2d and other ANMEs with different electron acceptors in the freshwater systems could provide the theorical fundament about AOM and carbon cycle in the freshwater, as well as the new insight on using ANMEs to simultaneously reduce CH4 and pollutants in the engineering application.

      CH4是仅次于CO2的第2大温室气体,对全球变暖的贡献已经达到20%[1,2],但CH4产生的温室效应大约是同物质量的CO2的20~30[3],并以每年0.5%~1%的速度增[4]。在自然界中,甲烷的代谢途径主要有甲烷好氧氧化和甲烷厌氧氧化(anaerobic methane oxidation,AOM)2大类,分别由甲烷好氧氧化菌和甲烷厌氧氧化菌介导完成。通常,甲烷好氧氧化被认为是甲烷代谢的主要途径,随后科学家却发现甲烷厌氧氧化削减了超过90%的海洋底层所产生的甲[5,6]和约50%淡水湿地产生的甲[7],使得最终进入大气的甲烷十分有限,因此,AOM在地球C循环过程中占有非常重要的地位,对于维持全球气候稳定也至关重[6,7]

      最早发现的甲烷厌氧氧化是发生在海洋中的以硫酸盐为电子受体的甲烷厌氧氧化(SAMO)[6],随着研究的深入,科学家们发现在淡水环境中存在以硝酸根/亚硝酸根为电子受体的甲烷厌氧氧化(DAMO)[8,9,10]。因此,甲烷厌氧氧化(AOM)的研究环境主要分为2大类:1) 海水中AOM的主要电子受体为硫酸盐或者铁、锰氧化物;2) 淡水系统中存在的硝酸盐或亚硝酸盐驱动的DAMO,也有硫酸盐、铁锰氧化物或者有机物(腐殖酸等)作为电子受体驱动的甲烷厌氧氧化反应。而除了NO2-驱动的AOM是由一种NC10门的Candidatus Methylomirabilis oxyfera细菌介导之外,关于该细菌的自然生境分布检[11,12,13,14]、富集培[15,16,17,18,19]、影响因[20,21,22,23]、电子转移途[20,21,22,23,24]以及分子生物学的研[14,21,25,26,27,28,29,30]较多,其他所有已发现的电子受体驱动的AOM均是由一类隶属于广古菌门的甲烷厌氧氧化古菌(archaeal anaerobic methanotrophs, ANMEs)完成的。这些甲烷厌氧氧化古菌可以在厌氧或者缺氧条件下,以甲烷作为碳源、能源以及电子供体,以硫酸根、硝酸根、铁化合物、锰氧化物、铬氧化物、硒酸盐、AQDS以及腐殖酸等作为电子受体,将甲烷氧化为二氧化碳或者碳酸盐的微生物化学过程。

      对海洋中AOM现象研究已经较多,由于其反应可利用电子受体较为单一(多为SO42-),研究多集中在ANMEs及相关硫酸盐还原菌(sulfate-reducing bacteria,SRB)之间的关系,相互之间的作用机理、反应推断、理论基础和相关环境因素研究也已较为完善。然而,近年来,研究发现淡水系统中(河流、湖泊、湿地、污水处理厂等)也存在ANMEs古菌介导下的AOM过程,且该过程单独或与其他生物反应耦合下的碳、氮、硫元素循环可能对淡水环境碳源与汇格局及过程具有重大意义。相对于海洋较为单一的环境条件,淡水系统环境更为复杂多变,电子受体繁多(SO42-NO2-NO3-、MnO2、Fe3+、Cr6+、硒酸盐、AQDS、腐殖酸等),受人为因素影响大,与ANMEs相关联的微生物的协同作用关系、生物地球化学效应和温室气体减排意义等还很少有研究报道。本研究系统梳理了ANMEs古菌介导下淡水系统的甲烷厌氧氧化过程及相关微生物协同作用机制,旨在为淡水系统甲烷减排及工程技术创新应用提供新的思路。

    • 1 甲烷厌氧氧化反应古菌群

    • 1.1 ANMEs古菌的分类

      AOM反应菌群通常根据系统发育分析情况分为ANME-1、ANME-2(a/b/c)、ANME-3等3类,均属于广古菌[31]。这3类古菌彼此间的进化距离较远,16S rRNA基因序列的相似度仅为75%~92%[6]。即使在ANME-2中,分枝ANME-2a、ANME-2b与ANME-2c相似度也较低,因此常将ANME-2a和ANME-2b合并归为ANME-2a/b[31]。ANME-1与Methanosarcinales (甲烷八叠球菌)/Methanomicrobiales (产甲烷微菌)相似但却独自形成一个新的分[32];ANME-2古菌隶属于Methanosarcinales (甲烷八叠球菌属)[6];ANME-3古菌与Methanococcoides (产甲烷球菌)相[6]。虽然ANME-1、ANME-2、ANME-3属于ANMEs不同的分支,但是都具有在各种生境中厌氧氧化甲烷的能[6]。而随着研究的进行,淡水系统中发现了一种新的ANMEs,被称为ANME-2d。ANME-2d属于ANMEs的亚簇,归属于Methanoperedens科,是ANME-2的一个新的分支——Candidatus Methanoperedens nitroreducens,与其他的ANME-2分支距离较远,ANME-2d被发现可以单独完成在厌氧条件下将NO3-还原成NO2-并同时氧化CH4的过程(nitrate-dependent AOM,N-AOM) (表1)[6]。HAROON[33]进一步通过宏基因组和转录组学分析表明ANME-2d确实只能将NO3-还原为NO2-。ANME-2d后来也被命名为GOM Arc I和AOM-associated archaea (AAA)[34]。ANME-2d也是自然界中唯一被发现可以利用NO3-作为电子受体进行AOM的古菌微生物,因此,在富含NO3-的淡水生态系统中,ANME-2d参与 N-AOM过程对淡水生态系统的碳、氮循环尤为关键,这也是近年来学者的研究热点之一。

      表1 甲烷与不同电子受体反应的吉布斯自由能

      Table 1 Gibbs energy of reactions between methane and relevant electron acceptors

      不同电子受体进行甲烷厌氧氧化的反应式自由能ΔG/(kJ·mol-1)
      5CH4+8MnO4+24H+→5CO2+8Mn2++22H2O-1 028.1
      3CH4+8NO2-+8H+→3CO2+4N2+10H2O-928.0
      3CH4+4Cr2O72-+32H+→8Cr3++3CO2+22H2O-878.8
      5CH4+8NO3-+8H+→5CO2+4N2+14H2O-765.0
      CH4+8Fe3++2H2O→CO2+8Fe2++8H+-454.6
      CH4+4AQDS+3H2O→HCO3-+H++4AQH2DS-41.0
      CH4+SO42-HCO3-+HS-+H2O-16.6
    • 1.2 ANME-1/2(a、b、c)/3古菌生理特性及自然生态分布

      ANME-1/2(a、b、c)/3均可介导完成海洋或淡水环境中的SAOM过[6]。ANME-1具有典型的杆形细胞形态,且在紫外光下能自发荧光,这是含有辅酶F420的产甲烷古菌的显著特[35]。ANME-1和ANME-3既可以单细胞形式存在,也可与硫酸盐还原菌(SRB)以共生体的形式存[35]。ANME-2则往往与硫酸盐还原菌(SRB)以外壳型或者混合型共生体存[35]。ANME-1/2(a、b、c)/3均是产甲烷古菌的进化分支,但到目前为止,还未获得任何单一ANMEs的纯培养[35]。ANME-1/2(a、b、c)/3微生物的生长缓慢,倍增时间长,一般为2~7个月,因此,富集时间长且难度大,限制了ANMEs的生理特性研[36]。有研究应用高甲烷分[37],也有研究通过添加石蜡油来增大甲烷的溶解度从而提高AOM反应速[38]

      FISH处理后,不同类型ANMEs的形[39,40]如图1所示。

      图1
                            FISH处理后不同类群ANMEs的形态

      图1 FISH处理后不同类群ANMEs的形态

      Fig. 1 Morphology of different groups of ANMEs after FISH treatment

      ANME-1/2(a、b、c)/3多分布在海洋冷泉区域,在淡水系统中,主要分布在极端环境如火山口、冰原、温泉等。这些微生物均为严格厌氧微生物,均不能在有氧的环境中生存,因此,到目前为止,并未在任何有氧环境中发现ANMEs的存在,其原因可能是由于ANMEs中含有对有氧环境极为敏感的[6]。ANME-1/2(a、b、c)/3主要分布特性如表2所示。

      表2 ANMEs分布及生理特性

      Table 2 Distribution and physiological characteristics of ANMEs

      古菌群隶属科目或相似科目发现区域特性
      ANME-1相似Methanosarcinales (甲烷八叠菌)/Methanomicrobiales (产甲烷微菌)火山口,深海等长方形,含有辅酶F420
      ANME-2a/b/c隶属Methanosarcinales (甲烷八叠球菌属)冷泉区域,黑海,部分淡水湿地,垃圾填埋场等球菌,与硫酸盐还原菌(SRB)形成混合细胞团且覆盖有机质膜(机理不清楚)
      ANME-3相似Methanococcoides (产甲烷球菌)极端环境(冰原或温泉等),火山口与SRB形成贝壳状细胞团
      ANME-2d隶属于Methanoperedens淡水环境如湿地、土壤、稻田、湖泊、河流、污水处理厂等不规则球菌,直径为1~3 μm左右
    • 1.3 ANME-2d古菌自然生态分布及生理特性

      ANME-2d古菌在自然界中发现较晚,但被发现广泛存在于各种淡水生境中,包括湿地沉积[8]、土壤和稻[40,41,42]、湖泊和河[40,41,42]以及污水处理[43]等。ANME-2d隶属于Methanoperedens科,为不规则球菌,直径为1~3 μm左右,一般以族群状态存在,最适温度为22~35 ℃、最适pH为7.0~8.0[8,10,27,33,44,45]。2006年,研究人员首次通过接种淡水沉积物在生物反应器中富集得到ANME-2d和可以还原NO2-N2并同时氧化的CH4M. oxyfera细菌的混合富集培养[8,10,27,33,44,45]。随后HU[29]也富集到含有ANME-2d古菌的培养物并且推断ANME-2d可能只能将硝酸根还原为亚硝酸根或者相比亚硝酸根ANME-2d古菌更优先利用硝酸根。HAROON[33]研究表明ANME-2d只能将硝酸盐还原为亚硝酸盐,而无法再继续将亚硝酸盐还原为氮气。因此,ANME-2d往往是与M. oxyfera共存于环境之中。但最新研究发现,ANME-2d具有解除由于NO2-浓度过高而产生的毒副作[10]。WEBER[46]在丹麦日德兰低硫高铁的Ørn湖的淡水沉积物中检测到了AOM活性,且证明了ANME-2d古菌主导完成了SAMO或Fe-AOM,也可能同时完成了SAMO和Fe-AOM。因此,ANME-2d古菌不仅存在于高硝酸盐环境中,在低硫高铁等其他电子受体丰富的淡水环境中也存在,这进一步佐证了ANME-2d对于淡水系统中甲烷排放控制的重要性。

      ANME-2d同样具有生长缓慢,倍增时间长等特点,难以进行纯培养物的富集和分离。HU[29]采用含淡水湖泊沉积物、消化污泥和活性污泥组成的混合污泥得到ANME-2d富集培养物,推断ANME-2d存在于一些淡水沉积物中。VAKSMAA[47]以意大利水稻田作为接种污泥经过2年的富集培养获得了含有ANME-2d的稳定富集培养物;ANME-2d的最大丰度达到系统总微生物的22%左右;宏基因测序结果表明ANME-2d含有反向产甲烷的以及硝酸盐还原的所有功能基因。研究人[48]在使用CH4作为燃料的微生物燃料电池(MFC)中研究发现MFC装置可以将ANME-2d古菌与M. oxyfera细菌分开。此外,为了进一步研究ANME-2d在不同生境中的分布以及丰度,提高检测手段以及灵敏度,进一步开展了ANME-2d的引物和探针的研[26,31,35,49,50]

      目前的研究通过分子生物学以及系统发育分析等手段证明了ANME-2d确实可以存在于多种生态环境中,但关于其作用机理及相关生态学意义的研究较少。由于ANME-2d在淡水环境中的广泛存在性,其对于全球淡水生态系统碳循环及温室效应的影响可能被严重忽视。

    • 2 ANMEs作用机制与电子转移途径

      与甲烷好氧氧化相比,在淡水系统中的甲烷厌氧氧化的研究较少。但是在淡水和陆地生态环境中,硫酸盐的浓度远低于海洋环境,且电子受体的种类也比较丰富。现在已发现的AOM根据电子受体类型主要可以分为以SO42-为电子受体的甲烷厌氧氧化(sulfate-dependent AOM,SAMO)、以NO3-/NO2-为电子受体的反硝化型甲烷厌氧氧化(denitrification anaerobic oxidation of methane,DAMO)和以金属氧化物(如Fe2O3和MnO2)为电子受体的甲烷厌氧氧化(metal-dependent AOM,metal-AOM) 3种类型。而研究表明,淡水系统中确实存在ANMEs古菌介导下的AOM现象,这使得ANMEs在淡水生态系统中电子受体选择机制成为当下ANMEs相关研究的热点之[51]

    • 2.1 淡水系统中ANMEs的电子受体选择机制

    • 2.1.1 适用于ANME-1/2(a、b、c)/3的电子受体

      SAMO被认为是连接全球碳硫循环的重要环节,研究表明ANME-1、ANME-2a/-2b/-2c、ANME-3均可驱动SAMO[6]。一般认为,SAMO主要存在于SO42-浓度较高的海洋沉积物环境中,在淡水系统中,当硫酸盐浓度低于0.2 mmol·L-1时SAMO反应将不存在;但是在硫酸盐较低的陆地和淡水生态系统等环境中均发现存在SAMO现[52]。SEGARRA[7]在淡水湿地中也发现硫酸盐电子受体为主导下多种电子受体共同驱动的AOM过程。因此,硫酸盐浓度可能不是制约SAMO过程的关键影响因素。一方面,古菌ANME-1、ANME-2和ANME-3通常与硫酸盐还原菌(SRB)形成密切的共生关[6,51],ANMEs古菌活化CH4,将电子传递给SRB,SRB进一步还原SO42-。另一方面,近年来MILUCKA[53]发现,ANMEs可单独实现甲烷厌氧氧化并将SO42-还原为硫单质(S),从而证明了SAMO不需要SRB协同作用。

      以Fe(III)为电子受体的Fe-AOM在淡水系统中广泛存[5,54,55,56,57,58,59,60,61,62]。2009年,BEAL[63]在湖底沉积物中发现了有微生物以Mn(IV)和Fe(III)作为电子受体对CH4进行厌氧氧化的现象,并推断ANME-1、ANME-3可能主导了该AOM反应过程。2013年,有学者研究淡水系统湖泊沉积物中甲烷厌氧氧化活性,证明了Fe-AOM反应在淡水系统中的存[59]。此外,SCHELLER[36]通过向含有ANME-2a和ANME-2c的SAMO富集培养物中分别添加铁的配合物(柠檬酸铁和乙二胺四乙酸铁)作为电子受体的体系中观察到了AOM现象,表明ANME-2a古菌和ANME-2c古菌可以Fe3+作为电子受体。

      金属矿物在反应自由能上要远大于硫酸盐(表1),在富含金属矿物质的矿山区域、地下潜水等区域,Metal-AOM可能比SAMO更易发生并起到主导作用。但是由于金属氧化物多以固体形式存在,在水体中溶解度非常小,反应的发生可能存在微生物不能有效接触电子供受体的制约性因素,其相关反应机理还鲜有研[64]。除此之外,腐殖酸以及AQDS也可以作为电子受体进行AOM过程,SCHELLER[36]在培养ANME-2a和ANME-2c时,首次报道ANMEs可以使用腐殖酸以及AQDS作为电子受体,突破了人们对AOM电子受体范围的认识。

    • 2.1.2 ANME-2d古菌电子受体的普适性

      长期以来,研究者获得的ANME-2d富集培养物均是在以硝酸盐为电子受体状态下富集培养得到的,ANME-2d也被认为是连接淡水系统碳氮循环的关键微生物。而最近的研究表明,ANME-2d可能是一种多功能的甲烷氧化菌,在不同的环境条件下能够利用不同的电子受[39]。ANME-2d古菌拥有大量编码细胞色素C的基[33,39],研究发现其与已知的铁还原菌Ferrroglobus placidus非常相似;因此,推测ANME-2d古菌可能介导沉积物中的Fe-AOM过[65]。ETTWIG[39]向含有ANME-2d的硝酸盐富集培养体系中添加Fe(III)和Mn(IV)矿物,在没有硝酸盐存在的条件下发现ANME-2d可以介导以铁锰为电子受体的AOM,进而推测ANME-2d可以通过选择不同的电子受体以适应环境的改变。FU[66]向由ANME-2d古菌主导的N-AOM的富集培养物中添加异化铁还原菌Shewanellaoneidensis MR-1获得混合培养物,在以水铁矿作为唯一的电子受体的混合培养物中也观察到了AOM现象,据此认为是ANME-2d古菌和异化金属还原菌共同完成了Fe-AOM反应。ETTWIG[39]向含有ANME-2d古菌(40%~50%)和M. oxyfera细菌(约40%)为主导的N-AOM培养物中分别添加柠檬酸铁、水铁矿和水钠锰矿,各培养物中均检测到了Metal-AOM的活性;此外,N-AOM培养物不含其他古细菌或已知的铁还原微生物。ETTWIG[67]也做了类似的研究,向由亚硝酸盐富集培养得到的仅由M.oxyfera (约80%)组成缺少ANME-2d的富集培养物中添加铁锰电子受体,但是并没有检测到Metal-AOM活性。这些研究表明,N-AOM富集培养物中的ANME-2d古菌可以介导Metal-AOM,无论是可溶性还是不溶性金属氧化[39]。而LU[68]研究了Cr-AOM微生物化学过程,研究表明ANME-2d古菌也可能单独或者与其他微生物协同驱动Cr(VI)-AOM,这更进一步地证明了ANME-2d可能具有介导Metal-AOM的能力。蔡朝[69]还研究了H2/CH4-MBfR还原SeO42-的微生物过程,首次证实了微生物能够以CH4作为唯一的电子供体驱动SeO42-介导的AOM过程。此研究结果拓宽了CH4在废水处理中的应用前景及价值,其生物学机理有待进一步研究。

      除了可以驱动Metal-AOM以外,ANME-2d古菌还被发现可以利用硫酸盐作为电子受体驱动SAMO。SCHUBERT[70]在缺少硝酸盐和亚硝酸盐的意大利Cadagno湖沉积物中发现了SAMO现象,并且ANME-2d是唯一检测到的甲烷厌氧氧化菌。此外,来自富含低盐水的ANME-2a/b和ANME-2d的培养物中SAMO也被检测到,但在向该富集培养物中添加硝酸盐、水铁矿、腐殖酸等其他电子受体均没有检测到AOM现象,因此,ANME-2d古菌被推测能够驱动SAMO[52]

      有研[39]表明,ANME-2d可以利用不同种类多种形式的电子受体,包括硝酸盐、硫酸盐、可溶高价金属离子,不溶金属氧化物等,这说明ANME-2d可以根据环境的不同进一步选择电子受体。因此,其相关的代谢途径,在面临不同类型不同形态的电子受体时,其相关的电子转移途径,与其他协同微生物之间的关系就是突破ANME-2d作用机制的关键性问题。

    • 2.2 ANME-2d古菌的电子转移机制

    • 2.2.1 硝酸盐作为电子受体的胞内电子转移机制

      ANME-2d古菌主要有3种可能的电子转移方式如图2所示。ANME-2d古菌可以独立完成硝酸盐驱动的甲烷厌氧氧化反应,而不需要其他微生物的参与,在氧化甲烷的同时可以将硝酸盐还原为亚硝酸盐,宏基因测序也表明了ANME-2d古菌不仅具有氧化甲烷的关键基因,还具有硝酸盐还原酶的基[31]。在ANME-2d古菌中发现的逆向产甲烷途径是在ANMEs古菌中首次发现的最为完整的逆向产甲烷途径,该途径包含了所有的编码甲基辅酶-M-还原酶(Mcr)亚基的基因(mcrABCDG)和编码N5N10-亚甲基-H4MPT还原酶(Mer)的基因(mer)[69]。到目前为止,ANME-2d古菌基因组测序分析所取得的培养物均来自生物反应器。在这些反应器中,ANME-2d古菌均是和NC10门细菌同时存在的,比如厌氧氨氧化细菌(Ca. Kueneniastuttgartiensis)[45]M. oxyfera[33,42,44]。这表明ANME-2d可能依赖这些细菌去除NO2-[45]。在N-AOM中,ANME-2d除了可以介导生成NO2-,还能通过合成一种c型亚硝酸盐还原酶(NrfAH)将产生的NO2-还原为NH4+,进而解除由于NO2-浓度过高而产生的毒副作用。因此,ANME-2d古菌具备单独解除过高NO2-的能力,而不需要M. oxyfera细菌的参[69]。即ANME-2d古菌可以单独完成硝酸根驱动的甲烷厌氧氧化,而不需要其他微生物协助完成电子转移或代谢相关中间产物。

      图2
                            ANME-2d古菌的3种电子转移方式

      图2 ANME-2d古菌的3种电子转移方式

      Fig. 2 Three electron transfer methods of ANME-2d

    • 2.2.2 金属氧化物等作为可选择电子受体的胞外电子转移机制

      ANME-2d不仅可以利用硝酸盐这种可溶电子受[33],ANME-2d可以参与SAMO过[69],还可以还原难溶的金属氧化物(Fe(III)、Mn(IV))以进行甲烷氧化;但这种难溶的电子受体如何被ANME-2d古菌利用,其电子转移机制是什么,现在还存在争论,主要的电子转移途径可能存在以下几种。

      1) 胞外电子直接转移(DEET)。与环境中其他相关的电子受体不一样,Fe(III)和Mn(IV)经常以不溶固体的形式存在,因此它们不能直接被转移到细胞[71]。ETTWIG[39]发现,ANME-2d可以单独完成Metal-AOM,且通过宏基因技术在其富集培养物中发现了比地杆菌属丰度更高的编码细胞色素C的蛋白基因。这些细胞色素C被认为是地杆菌属等异化金属还原菌进行DEET反应过程必须的导电介[72,73],可以进行胞外电子的转移过程。同时通过对比实验,发现在硝酸盐富集环境中ANME-2d细胞色素C基因的表达非常低,这说明细胞色素C在Metal-AOM电子转移中起到至关重要的作[65]。因此,研究者推断ANME-2d在驱动Metal-AOM时的电子转移方式可能是像异化金属还原菌一样通过直接电子转移(DEET)来进行[71]。除此之外,研究者发现在ANME-1、ANME-2a等古菌中也发现了编码细胞色素C的基因,而这些基因的表达和金属还原之间的关系还有待证明。显然Metal-AOM的电子转移方式将比单纯异化金属还原的过程要复杂的多。有关ANME-2d在不同电子受体条件下的细胞色素C的表达仍需探[73,74]

      2) 种间电子转移机制(DIET)。ANMEs被发现时被证明是和SRB协同完成甲烷氧化和硫酸盐还原的过程,MILUCKA[53]提出以硫酸根作为电子受体的SAOM反应是由ANMEs古菌独立完成的。WANKEL[75]则证明了ANME-2古菌的分支单独完成了以硫酸盐还原的零价硫作为为中间载体的AOM全过程。对于ANME-2d这种特殊的ANMEs古菌,其与其他微生物之间的关联也一直是科学家们关注的热点问题。

      FU[66]向N-AOM的富集培养物(由ANME-2d主导)中添加异化铁还原菌Shewanellaoneidensis MR-1获得混合培养物,发现了2种微生物在培养过程中丰度均有所增加,并推测2种微生物可能是通过电子穿梭体、细胞色素蛋白载体、纳米导线等方式协同完成Metal-AOM电子转移的过程。LU[68]通过在ANME-2d富集培养物中加入Cr(VI)也发现了甲烷氧化伴随Cr(VI)还原的过程,推测可能是ANME-2d和一种未知的Cr(VI)还原微生物共同完成了Cr(VI)-AOM的过程。而其完成方式可能是通过DIET种间电子转移方式完成。相较于常规的电子转移体系,DIET由于不需要中间电子传递体作为电子载体,而直接通过微生物自身的酶或者导电鞭毛等作为介体,省去了生成中间产物时所需要的酶和能量等。由于AOM反应的活化能要远低于甲烷好氧氧化,所以DIET相较于其他电子转移方式可能更加适合ANMEs古菌与其他微生物协同完成甲烷的氧化过程。

      本研究以2种锰矿物电子受体(天然锰矿粉;人工合成δ-MnO2)和2种不同接种污泥(锰矿石人工湿地污泥;由污水厂厌氧段污泥、河流底泥以及水稻田土壤所组成的混合污泥),以甲烷作为唯一电子供体,超过700 d的富集培养,首次在富集系统中获得了4种锰矿物电子受体驱动的具有甲烷厌氧氧化效果的富集培养物。在进行以锰矿为电子受体的甲烷厌氧氧化富集培养过程中也发现了ANME-2d古菌和异化金属还原菌共存的现象,并且通过qPCR、FISH等手段发现在连续培养过程中2种微生物的绝对丰度均呈现增长的趋势。研究结果证明了锰氧化物可以耦合AOM反应,并且ANME-2d和异化金属还原菌可能共同驱动了Mn-AOM反应。

      电子可以从ANMEs微生物转移到与矿物质相关的金属离子上,反之亦然;由于微生物的细胞膜在生理上说来是不可渗透的并且矿物质也不是导电的,因此,微生物必须发展出与细胞外矿物质交换电子(如c型细胞色素和微生物纳米导线)的能力的分子机制,即胞外电子转移机[75]。关于ANME-2d的电子转移机制,根据不同的电子受体环境,可能呈现出不同的电子转移方[64]。在以硝酸盐为电子受体时,ANME-2d可以通过逆向产甲烷途径独立完成甲烷氧化和硝酸盐还原的过程,而在与其他电子受体如金属氧化物等难以进入细胞体内的电子受体,则可能要通过编码细胞色素C等胞外电子载体来进行电子转移过[39]。这也说明ANME-2d的电子转移机制可能并不是固定的,而是随着电子受体环境的改变而改变,自然环境中的电子受体多时可能需要通过与其他微生物协同完成甲烷厌氧氧化过程。

    • 3 结论与展望

      1) 淡水系统是地球重要的温室气体排放源,而作为在淡水系统中广泛存在的ANMEs古菌对于温室气体效应的减缓和碳元素循环具有重要意义。国内外学者对ANMEs介导下不同电子受体AOM反应进行了大量的研究,这些反应或由ANMEs单独完成,或与其他微生物协同完成,而其相关作用机制尚未明晰。深入研究ANMEs在淡水系统中的作用机制及相关分子生物学机理是明晰淡水系统元素循环和实现甲烷减排的关键。

      2) 目前污水处理技术面临2大主要问题:污水中碳源不足难以实现脱氮过程以及污水处理过程中衍生的大量温室气体CH4的排放。而ANMEs古菌可以同步去除甲烷、氮素和高价金属离子等且不需要额外昂贵的电子供体如乙酸和甲醇等,具有潜在的应用前景。并且有研究报道表明ANMEs可以单独或者协同其他异化金属还原菌去除重金属镉、砷高价化合物,最新研究发现ANMEs可以用于处理染料废水。

      3) ANMEs古菌倍增时间较长,生长缓慢,是否有可能应用到污水处理过程中,仍需要进一步对ANMEs相关反应机理和培养条件进行进一步研究和优化。未来的研究可以着重于缩短ANMEs的培养周期并且增强AOM反应速率,揭示ANMEs的生理特性、作用机制、电子转移途径等,以期实现低能耗、低风险的生态污水处理方式。

      4) 到目前为止,关于ANME-2d富集培养物报道的研究较少,ANME-2d的富集培养物也远远少于需要用来研究的原材料。而ANME-2d独特的电子受体选择性和电子转移机制决定其在淡水生境的重要地位。未来研究可以关注ANME-2d的工程应用价值,如与厌氧氨氧化细菌耦合同步实现氨氮和硝酸盐氮的去除,还可以用于难降解有机物处理如PPCPs等,应用前景较为广泛。

      5) 淡水生境是目前学者重点研究的对象,但目前发现的ANMEs多存在于天然生境中,而在人为影响下的大坝水库、库区消落带等也是甲烷排放潜在来源,而关于人为生境内ANMEs研究还鲜有报道。今后的研究可以关注不同人为淡水生态系统中ANMEs存在可能性及作用过程,对人为生境建成后的生态恢复提供必要的支撑。

    • 参考文献

      • 1

        CAI Y F, ZHENG Y, BODELIER P L, et al. Conventional methanotrophs are responsible for atmospheric methane oxidation in paddy soils[J]. Nature Communications, 2016, 7: 1-10.

      • 2

        SU J, HU C, YAN X, et al. Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice[J]. Nature, 2015, 523(7562): 602-606.

      • 3

        RHEE T S, KETTLE A J, ANDREAE M O. Methane and nitrous oxide emissions from the ocean: A reassessment using basin-wide observations in the Atlantic[J]. Journal of Geophysical Research Atmospheres, 2009, 114: 1-20.

      • 4

        TAMAI N, TAKENAKA C, ISHIZUKA S. Water-soluble Al inhibits methane oxidation at atmospheric concentration levels in Japanese forest soil[J]. Soil Biology & Biochemistry, 2007, 39(7): 1730-1736.

      • 5

        BAROR I, ELVERT M, ECKERT W, et al. Iron-coupled anaerobic oxidation of methane performed by a mixed bacterial-archaeal community based on poorly-reactive minerals[J]. Environmental Science & Technology, 2017, 51(21): 12293-12301.

      • 6

        KNITTEL K, BOETIUS A. Anaerobic oxidation of methane: Progress with an unknown process[J]. Annual Review of Microbiology, 2008, 63: 311-334.

      • 7

        SEGARRA K E, SCHUBOTZ F, SAMARKIN V, et al. High rates of anaerobic methane oxidation in freshwater wetlands reduce potential atmospheric methane emissions[J]. Nature Communications, 2015, 6: 1-8.

      • 8

        RAGHOEBARSING A A, OL A, PASSCHOONEN K T V D, et al. A microbial consortium couples anaerobic methane oxidation to denitrification[J]. Nature, 2006, 440(7086): 918-921.

      • 9

        ISLAS-LIMA S, THALASSO F, GÓMEZ-HERNANDEZ J. Evidence of anoxic methane oxidation coupled to denitrification[J]. Water Research, 2004, 38(1): 13-16.

      • 10

        HU S, ZENG R J, BUROW L C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.

      • 11

        SHEN L D, WU H S, LIU X, et al. Cooccurrence and potential role of nitrite- and nitrate-dependent methanotrophs in freshwater marsh sediments[J]. Water Research, 2017, 123: 162-172.

      • 12

        PADILLA C C, RISTOW L A, SARODE N. NC10 bacteria in marine oxygen minimum zones[J]. ISME Journal, 2016, 10(8): 2067-2071.

      • 13

        WANG Y, HUANG P, YE F, et al. Nitrite-dependent anaerobic methane oxidizing bacteria along the water level fluctuation zone of the Three Gorges Reservoir[J]. Applied Microbiology & Biotechnology, 2016, 100(4): 1977-1986.

      • 14

        CHEN J, ZHOU Z, GU J D. Complex community of nitrite-dependent anaerobic methane oxidation bacteria in coastal sediments of the Mai Po wetland by PCR amplification of both 16S rRNA and pmoA genes[J]. Applied Microbiology & Biotechnology, 2015, 99(3): 1463-1473.

      • 15

        柴风光, 卢培利, 李微薇, 等. 利用硝酸盐和亚硝酸盐同步富集厌氧甲烷氧化微生物的比较实验[J]. 微生物学通报, 2018, 45(4): 762-770.

      • 16

        HU B L, HE Z F, GENG S, et al. Cultivation of nitrite-dependent anaerobic methane-oxidizing bacteria: Impact of reactor configuration[J]. Applied Microbiology & Biotechnology, 2014, 98(18): 7983-7991.

      • 17

        HATAMOTO M, KIMURA M, SATO T, et al. Enrichment of denitrifying methane-oxidizing microorganisms using up-flow continuous reactors and batch cultures[J]. Plos One, 2014, 9(12): 1-12.

      • 18

        ZHU B, VAN D G, FRITZ C, et al. Anaerobic oxidization of methane in a minerotrophic peatland: Enrichment of nitrite-dependent methane-oxidizing bacteria[J]. Applied & Environmental Microbiology, 2012, 78(24): 8657-8665.

      • 19

        LUESKEN F A, ALEN T A V, BIEZEN E V D, et al. Diversity and enrichment of nitrite-dependent anaerobic methane oxidizing bacteria from wastewater sludge[J]. Applied & Environmental Microbiology, 2011, 92(4): 845-854.

      • 20

        HE Z F, CAI C, SHEN L D, et al. Effect of inoculum sources on the enrichment of nitrite-dependent anaerobic methane-oxidizing bacteria[J]. Applied Microbiology & Biotechnology, 2015, 99(2): 939-946.

      • 21

        HE Z F, GENG S, PAN Y W, et al. Improvement of the trace metal composition of medium for nitrite-dependent anaerobic methane oxidation bacteria: Iron (II) and copper (II) make a difference[J]. Water Research, 2015, 85: 235-243.

      • 22

        YAN P G, LI M C, WEI G S, et al. Molecular fingerprint and dominant environmental factors of nitrite-dependent anaerobic methane-oxidizing bacteria in sediments from the Yellow River estuary, China[J]. Plos One, 2015, 10(9): 1-14.

      • 23

        HU S, ZENG R J, KELLER J, et al. Effect of nitrate and nitrite on the selection of microorganisms in the denitrifying anaerobic methane oxidation process[J]. Environmental Microbiology Reports, 2011, 3(3): 315-319.

      • 24

        MING L W, ETTWIG K F, JETTEN M S M, et al. A new intra-aerobic metabolism in the nitrite-dependent anaerobic methane-oxidizing bacterium Candidatus Methylomirabilis oxyfera[J]. Biochemical Society Transactions, 2011, 39(1): 243-248.

      • 25

        HE Z F, CAI C Y, WANG J Q, et al. A novel denitrifying methanotroph of the NC10 phylum and its microcolony[J]. Scientific Reports, 2016, 6: 1-10.

      • 26

        HE Z F, WANG J Q, HU J J, et al. Improved PCR primers to amplify 16S rRNA genes from NC10 bacteria[J]. Applied Microbiology & Biotechnology, 2016, 100(11): 5099-5108.

      • 27

        HE Z F, CAI C, GENG S, et al. Mdodeling a nitrite-dependent anaerobic methane oxidation process: Parameters identification and model evaluation[J]. Bioresource Technology, 2013, 147(8): 315-320.

      • 28

        ETTWIG K F, BUTLER M K, LE PASLIER D, et al. Nitrite-driven anaerobic methane oxidation by oxygenic bacteria[J]. Nature, 2010, 464(7288): 543-548.

      • 29

        HU S, ZENG R J, BUROW L C, et al. Enrichment of denitrifying anaerobic methane oxidizing microorganisms[J]. Environmental Microbiology Reports, 2010, 1(5): 377-384.

      • 30

        ETTWIG K F, ALEN T V, PASSCHOONEN K T V D, et al. Enrichment and molecular detection of denitrifying methanotrophic bacteria of the NC10 phylum[J]. Applied Microbiology & Biotechnology, 2009, 75(11): 3656-3662.

      • 31

        TIMMERS P H A, WIDJAJA-GREEFKES H C A, PLUGGE C M, et al. Evaluation and optimization of PCR primers for selective and quantitative detection of marine ANME subclusters involved in sulfate-dependent anaerobic methane oxidation[J]. Applied Microbiology & Biotechnology, 2017, 14: 1-13.

      • 32

        HINRICHS K U, HAYES J M, SYLVA S P, et al. Methane-consuming archaebacteria in marine sediments[J]. Nature, 1999, 398(6730): 802-805.

      • 33

        HAROON M F, SHIHU H, YING S, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.

      • 34

        TIMMERS P H A, WELTE C U, KOEHORST J J, et al. Reverse methanogenesis and respiration in methanotrophic archaea[J]. Archaea, 2017, 17: 1-22.

      • 35

        周京勇, 刘冬秀, 何池全, 等. 土壤中甲烷厌氧氧化菌多样性的分子检测[J]. 生态学报, 2015, 35(11): 3491-3503.

      • 36

        SCHELLER S, YU H, CHADWICK G L, et al. Artificial electron acceptors decouple archaeal methane oxidation from sulfate reduction[J]. Science, 2016, 351(6274): 703-707.

      • 37

        陈颖. 厌氧甲烷氧化微生物代谢分子机制及其潜在参与矿物形成机理的研究[D]. 上海: 上海交通大学, 2014.

      • 38

        FU L, DING Z W, DING J, et al. The role of paraffin oil on the interaction between denitrifying anaerobic methane oxidation and Anammox processes[J]. Applied Microbiology & Biotechnology, 2015, 99(19): 7925-7936.

      • 39

        ETTWIG K F, ZHU B, SPETH D, et al. Archaea catalyze iron-dependent anaerobic oxidation of methane[J]. Proceedings of the National Academy of Sciences ,2016, 113(45): 12792-12796.

      • 40

        DING L J, SU J Q, XU H J, et al. Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing[J]. ISME Journal, 2015, 9(3): 721-734.

      • 41

        VAKSMAA A, LÜKE C, ALEN T V, et al. Distribution and activity of the anaerobic methanotrophic community in a nitrogen-fertilized Italian paddy soil[J]. FEMS Microbiology Ecology, 2016, 92(12): 1-11.

      • 42

        SEIFERT R, NAUHAUS K, BLUMENBERG M, et al. Methane dynamics in a microbial community of the Black Sea traced by stable carbon isotopes in vitro[J]. Organic Geochemistry, 2006, 37(10): 1411-1419.

      • 43

        DING Z W, DING J, FU L, et al. Simultaneous enrichment of denitrifying methanotrophs and anammox bacteria[J]. Applied Microbiology & Biotechnology, 2014, 98(24): 10211-10221.

      • 44

        HE Z F, GENG S, SHEN L D, et al. The short- and long-term effects of environmental conditions on anaerobic methane oxidation coupled to nitrite reduction[J]. Water Research, 2015, 68(47): 554-562.

      • 45

        HAROON M F, HU S, SHI Y, et al. Anaerobic oxidation of methane coupled to nitrate reduction in a novel archaeal lineage[J]. Nature, 2013, 500(7464): 567-570.

      • 46

        WEBER H S, HABICHT K S, THAMDRUP B. Anaerobic methanotrophic archaea of the ANME-2d cluster are active in a low-sulfate, iron-rich freshwater sediment[J]. Frontiers in Microbiology, 2017, 8: 1-13.

      • 47

        VAKSMAA A, JETTEN M S M, ETTWIG K F, et al. McrA primers for the detection and quantification of the anaerobic archaeal methanotroph Candidatus Methanoperedens nitroreducens[J]. Applied Microbiology & Biotechnology, 2017, 101(4): 1631-1641.

      • 48

        DING J, LU Y Z, FU L, et al. Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell[J]. Water Research, 2016, 110: 112-119.

      • 49

        VAKSMAA A, GUERRERO-CRUZ S, ALEN T A V, et al. Enrichment of anaerobic nitrate-dependent methanotrophic Candidatus Methanoperedens nitroreducens archaea from an Italian paddy field soil[J]. Applied Microbiology & Biotechnology, 2017, 101(18): 7075-7084.

      • 50

        AI M, MOCHIMARU H, KAZAMA H, et al. Development of 16S rRNA gene-targeted primers for detection of archaeal anaerobic methanotrophs (ANMEs)[J]. FEMS Microbiology Letters, 2010, 297(1): 31-37.

      • 51

        STROUS M, JETTEN M S M. Anaerobic oxidation of methane and ammonium[J]. Annual Review of Microbiology, 2004, 58(1): 99-117.

      • 52

        TIMMERS P H, SUAREZZULUAGA D A, ROSSEM M V, et al. Anaerobic oxidation of methane associated with sulfate reduction in a natural freshwater gas source[J]. ISME Journal, 2016, 10(6): 1400-1412.

      • 53

        MILUCKA J, FERDELMAN T G, POLERECKY L, et al. Zero-valent sulphur is a key intermediate in marine methane oxidation[J]. Nature, 2012, 491(7425): 541-546.

      • 54

        WICKLAND K, HAMDAN L, ROOZE J, et al. Iron‐dependent anaerobic oxidation of methane in coastal surface sediments: Potential controls and impact[J]. Limnology & Oceanography, 2016, 61: S267-S282.

      • 55

        EGGER M, RASIGRAF O, SAPART C J, et al. Iron-mediated anaerobic oxidation of methane in brackish coastal sediments[J]. Environmental Science & Technology, 2015, 49(1): 277-283.

      • 56

        HANSEL C M, LENTINI C J, TANG Y, et al. Dominance of sulfur-fueled iron oxide reduction in low-sulfate freshwater sediments[J]. ISME Journal, 2015, 9(11): 2400-2412.

      • 57

        RIEDINGER N, FORMOLO M J, LYONS T W, et al. An inorganic geochemical argument for coupled anaerobic oxidation of methane and iron reduction in marine sediments[J]. Geobiology, 2014, 12(2): 172-181.

      • 58

        TORRES N T, OCH L M, HAUSER P C, et al. Early diagenetic processes generate iron and manganese oxide layers in the sediments of Lake Baikal, Siberia[J]. Environmental Science Processes & Impacts, 2014, 16(4): 879-889.

      • 59

        NORDI K Á, BO T, SCHUBERT C J. Anaerobic oxidation of methane in an iron-rich Danish freshwater lake sediment[J]. Limnology & Oceanography, 2013, 58(2): 546-554.

      • 60

        AMOS R T, BEKINS B A, COZZARELLI I M, et al. Evidence for iron-mediated anaerobic methane oxidation in a crude oil-contaminated aquifer[J]. Geobiology, 2012, 10(6): 506-517.

      • 61

        HOLMKVIST L, FERDELMAN T G, BO B J. A cryptic sulfur cycle driven by iron in the methane zone of marine sediment (Aarhus Bay, Denmark) [J]. Geochimica Et Cosmochimica Acta, 2011, 75(12): 3581-3599.

      • 62

        SIVAN O, ADLER M, PEARSON A, et al. Geochemical evidence for iron‐mediated anaerobic oxidation of methane[J]. Limnology & Oceanography, 2011, 56(4): 1536-1544.

      • 63

        BEAL E J, HOUSE C H, ORPHAN V J. Manganese- and iron-dependent marine methane oxidation[J]. Science, 2009, 325(5937): 184-187.

      • 64

        HE Z F, ZHANG Q Y, FENG Y D, et al. Microbiological and environmental significance of metal-dependent anaerobic oxidation of methane[J]. Science of the Total Environment, 2017, 610-611: 759-768.

      • 65

        Arslan A, Speth D R, De G R M, et al. A metagenomics-based metabolic model of nitrate-dependent anaerobic oxidation of methane by Methanoperedens-like archaea[J]. Frontiers in Microbiology, 2015, 6: 1-14.

      • 66

        FU L, LI S W, DING Z W, et al. Iron reduction in the DAMO/Shewanellaoneidensis MR-1 coculture system and the fate of Fe(II)[J]. Water Research, 2016, 88: 808-815.

      • 67

        ETTWIG K F, SHIMA S, VAN P S, et al. Denitrifying bacteria anaerobically oxidize methane in the absence of archaea[J]. Environmental Microbiology, 2010, 10(11): 3164-3173.

      • 68

        LU Y Z, FU L, DING J, et al. Cr (VI) reduction coupled with anaerobic oxidation of methane in a laboratory reactor[J]. Water Research, 2016, 102: 445-452.

      • 69

        蔡朝阳. 潮间带古菌介导的甲烷厌氧氧化过程研究[D]. 杭州: 浙江大学, 2017.

      • 70

        SCHUBERT C J, FRANCISCO V, TINA L S B, et al. Evidence for anaerobic oxidation of methane in sediments of a freshwater system (Lago di Cadagno) [J]. FEMS Microbiology Ecology, 2015, 76(1): 26-38.

      • 71

        ONI O E, FRIEDRICH M W. Metal oxide reduction linked to anaerobic methane oxidation[J]. Trends in Microbiology, 2017, 25(2): 88-90.

      • 72

        WANG F, ZHANG Y, CHEN Y, et al. Methanotrophic archaea possessing diverging methane-oxidizing and electron-transporting pathways[J]. ISME Journal, 2014, 8(5): 1069-1078.

      • 73

        SHI L, SQUIER T C, ZACHARA J M, et al. Respiration of metal (hydr)oxides by shewanella and geobacter: A key role for multihaem c-type cytochromes[J]. Molecular Microbiology, 2010, 65(1): 12-20.

      • 74

        SHI L, DONG H L, REGUERA G, et al. Extracellular electron transfer mechanisms between microorganisms and minerals[J]. Nature Reviews Microbiology, 2016, 14(10): 651-662.

      • 75

        WANKEL S D, ADAMS M, JOHNSTON D T, et al. Anaerobic methane oxidation in metalliferous hydrothermal sediments: Influence on carbon flux and decoupling from sulfate reduction[J]. Environmental Microbiology, 2012, 14(10): 2726-2740.

参考文献 (75)

返回顶部

目录

/

返回文章
返回