結(jié)論

本研究的結(jié)果表明，當(dāng)存在一個以上的電子受體時，生物膜中的呼吸和代謝生理分層情況。 雖然莧菜紅還原與陽極競爭電子，但脫色鏈球菌菌株S12同時與陽極和莧菜紅呼吸。 此外，MFCs陽極室中出現(xiàn)了空間分離的呼吸模式。 浮游細胞和外層生物膜細胞傾向于使用莧菜紅作為電子受體，而內(nèi)層生物膜細胞傾向于使用陽極作為電子受體。 與僅用陽極呼吸的生物膜相比，額外的莧菜紅呼吸驅(qū)散了生物膜中的質(zhì)子積累。 陽極呼吸生物膜的氧化還原電位呈現(xiàn)先降低后升高的趨勢，這與其介質(zhì)占主導(dǎo)地位的性質(zhì)相一致。 額外的莧菜呼吸對生物膜電位影響較小，但陽極電位顯著降低。 與使用唯一電子受體呼吸的生物膜相比，由于生物膜內(nèi)的雙向呼吸電子轉(zhuǎn)移，同時使用莧菜紅和陽極呼吸的生物膜中觀察到更高和更均勻的活性分布。 雖然莧菜紅還原與陽極競爭電子，但脫色鏈球菌菌株S12同時與陽極和莧菜紅呼吸。此外，MFCs陽極室中出現(xiàn)了空間分離的呼吸模式。浮游細胞和外層生物膜細胞傾向于使用莧菜紅作為電子受體，而內(nèi)層生物膜細胞傾向于使用陽極作為電子受體。與僅用陽極呼吸的生物膜相比，額外的莧菜紅呼吸驅(qū)散了生物膜中的質(zhì)子積累。陽極呼吸生物膜的氧化還原電位呈現(xiàn)先降低后升高的趨勢，這與其介質(zhì)占主導(dǎo)地位的性質(zhì)相一致。額外的莧菜呼吸對生物膜電位影響較小，但陽極電位顯著降低。與使用唯一電子受體呼吸的生物膜相比，由于生物膜內(nèi)的雙向呼吸電子轉(zhuǎn)移，同時使用莧菜紅和陽極呼吸的生物膜中觀察到更高和更均勻的活性分布。

關(guān)聯(lián)內(nèi)容

支持信息

圖S1 ? S7。 此材料可通過互聯(lián)網(wǎng)免費獲取，網(wǎng)址為 http://pubs.acs.org.

作者信息

通訊作者

*電話：+862087684471。 傳真：+862087684587。 電郵： xumy@gdim.cn.

作者貢獻

Y.Y.，M.X.和G.S.設(shè)計了實驗。 Y.Y.和Y.X.進行了實驗。 Y.Y.，W.-M.W.，和M.X.分析數(shù)據(jù)并撰寫手稿。

筆記

作者聲明沒有相互競爭的經(jīng)濟利益。

致謝

我們感謝Joy D.Van Nostrand博士對語言修訂的熱情幫助。 本研究得到中國國家基礎(chǔ)研究計劃（973計劃）（2012CB22307）、中國廣東自然科學(xué)基金（S2013010014596）、國家自然科學(xué)基金（51422803, 31200096）、廣東科學(xué)院優(yōu)秀學(xué)者課題（RCJJ201502）的資助。 廣東省海洋經(jīng)濟區(qū)域創(chuàng)新發(fā)展示范項目（GD2012-D01-002）。

參考資料

(1) Kato, S.; Hashimoto, K.; Watanabe, K. Microbial interspecies electron transfer via electric currents through conductive minerals. Proc. Natl. Acad. Sci. U.S.A. 2012, 109 (25), 10042?10046.

(2) Pfeffer, C.; Larsen, S.; Song, J.; Dong, M.; Besenbacher, F.; Meyer, R. L.; Kjeldsen, K. U.; Schreiber, L.; Gorby, Y. A.; El-Naggar, M. Y.; Leung, K. M.; Schramm, A.; Risgaard-Petersen, N.; Nielsen, L. P. Filamentous bacteria transport electrons over centimetre distances. Nature 2012, 491 (7423), 218?221.

(3) Cunningham, J. A.; Rahme, H.; Hopkins, G. D.; Lebron, C.; Reinhard, M. Enhanced in situ bioremediation of BTEX contaminated groundwater by combined injection of nitrate and sulfate. Environ. Sci. Technol. 2001, 35 (8), 1663?1670.

(4) Finneran, K. T.; Lovley, D. R. Anaerobic degradation of methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA). Environ. Sci. Technol. 2001, 35 (9), 1785?1790.

(5) Xu, M.; Zhang, Q.; Xia, C.; Zhong, Y.; Sun, G.; Guo, J.; Yuan, T.; Zhou, J.; He, Z. Elevated nitrate enriches microbial functional genes for potential bioremediation of complexly contaminated sediments. ISME J. 2014, 8 (9), 1932?1944.

(6) Tender, L. M.; Reimers, C. E.; Stecher, H. A.; Holmes, D. E.; Bond, D. R.; Lowy, D. A.; Pilobello, K.; Fertig, S. J.; Lovley, D. R. Harnessing microbially generated power on the seafloor. Nat. Biotechnol. 2002, 20 (8), 821?825.

(7) Donovan, C.; Dewan, A.; Heo, D.; Beyenal, H. Batteryless, wireless sensor powered by a sediment microbial fuel cell. Environ. Sci. Technol. 2008, 42 (22), 8591?8596.

(8) Morris, J. M.; Jin, S. Influence of NO3 and SO4 on power generation from microbial fuel cells. Chem. Eng. J. 2009, 153 (1?3), 127?130.

(9) Yang, Y.; Xiang, Y.; Xia, C.; Wu, W. M.; Sun, G.; Xu, M. Physiological and electrochemical effects of different electron acceptors on bacterial anode respiration in bioelectrochemical systems. Bioresour. Technol. 2014, 164, 270?275.

(10) Parameswaran, P.; Torres, C. I.; Lee, H. S.; Krajmalnik-Brown, R.; Rittmann, B. E. Syntrophic interactions among anode respiring bacteria (ARB) and non-ARB in a biofilm anode: Electron Balances. Biotechnol. Bioeng. 2009, 103 (3), 513?523.

(11) Huang, L. P.; Gan, L. L.; Wang, N.; Quan, X.; Logan, B. E.; Chen, G. H. Mineralization of pentachlorophenol with enhanced degradation and power generation from air cathode microbial fuel cells. Biotechnol. Bioeng. 2012, 109 (9), 2211?2221.

(12) Wu, D.; Xing, D.; Lu, L.; Wei, M.; Liu, B.; Ren, N. Ferric iron enhances electricity generation by Shewanella oneidensis MR-1 in MFCs. Bioresour. Technol. 2013, 135, 630?634.

(13) Snider, R. M.; Strycharz-Glaven, S. M.; Tsoi, S. D.; Erickson, J. S.; Tender, L. M. Long-range electron transport in Geobacter sulfurreducens biofilms is redox gradient-driven. Proc. Natl. Acad. Sci. U.S.A. 2012, 109 (38), 15467?15472.

(14) Malvankar, N. S.; Vargas, M.; Nevin, K. P.; Franks, A. E.; Leang, C.; Kim, B.-C.; Inoue, K.; Mester, T.; Covalla, S. F.; Johnson, J. P.; Rotello, V. M.; Tuominen, M. T.; Lovley, D. R. Tunable metallic-like conductivity in microbial nanowire networks. Nat. Nano 2011, 6 (9), 573?579.

(15) Strycharz-Glaven, S. M.; Snider, R. M.; Guiseppi-Elie, A.; Tender, L. M. On the electrical conductivity of microbial nanowires and biofilms. Energy Environ. Sci. 2011, 4 (11), 4366?4379.

(16) Renslow, R. S.; Babauta, J. T.; Dohnalkova, A. C.; Boyanov, M. I.; Kemner, K. M.; Majors, P. D.; Fredrickson, J. K.; Beyenal, H. Metabolic spatial variability in electrode-respiring Geobacter sulfurreducens biofilms. Energy Environ. Sci. 2013, 6 (6), 1827?1836.

(17) Babauta, J. T.; Nguyen, H. D.; Beyenal, H. Redox and pH Microenvironments within Shewanella oneidensis MR-1 biofilms reveal an electron transfer mechanism. Environ. Sci. Technol. 2011, 45 (15), 6654?6660.

(18) Babauta, J. T.; Nguyen, H. D.; Harrington, T. D.; Renslow, R.; Beyenal, H. pH, redox potential and local biofilm potential microenvironments within Geobacter sulfurreducens biofilms and their roles in electron transfer. Biotechnol. Bioeng. 2012, 109 (10), 2651? 2662.

(19) Franks, A. E.; Glaven, R. H.; Lovley, D. R. Real-time spatial gene expression analysis within current-producing biofilms. ChemSusChem 2012, 5 (6), 1092?1098.

(20) Xu, M. Y.; Guo, J.; Kong, X. Y.; Chen, X. J.; Sun, G. P. Fe(III)- enhanced azo reduction by Shewanella decolorationis S12. Appl. Microbial. Biotechnol. 2007, 74 (6), 1342?1349.

(21) Hong, Y. G.; Xu, M. Y.; Guo, J.; Xu, Z. C.; Chen, X. J.; Sun, G. P. Respiration and growth of Shewanella decolorationis S12 with an azo compound as the sole electron acceptor. Appl. Environ. Microbiol. 2007, 73 (1), 64?72.

(22) Read, S. T.; Dutta, P.; Bond, P. L.; Keller, J.; Rabaey, K. Initial development and structure of biofilms on microbial fuel cell anodes. BMC Microbiol. 2010, 10, 98.

(23) Schrott, G. D.; Ordonez, M. V.; Robuschi, L.; Busalmen, J. P. Physiological stratification in electricity-producing biofilms of Geobacter sulfurreducens. ChemSusChem 2014, 7 (2), 598?603.

(24) Yang, Y.; Guo, J.; Sun, G.; Xu, M. Characterizing the snorkeling respiration and growth of Shewanella decolorationis S12. Bioresour. Technol. 2013, 128, 472?478.

(25) Teal, T. K.; Lies, D. P.; Wold, B. J.; Newman, D. K. Spatiometabolic stratification of Shewanella oneidensis biofilms. Appl. Environ. Microbial. 2006, 72 (11), 7324?7330.

(26) Nielsen, L. P.; Risgaard-Petersen, N.; Fossing, H.; Christensen, P. B.; Sayama, M. Electric currents couple spatially separated biogeochemical processes in marine sediment. Nature 2010, 463 (7284), 1071?1074.

(27) Yuan, Y.; Zhou, S. G.; Tang, J. H. In situ investigation of cathode and local biofilm microenvironments reveals important roles of OH- and oxygen transport in microbial fuel cells. Environ. Sci. Technol. 2013, 47 (9), 4911?4917.

(28) Rabaey, K.; Verstraete, W. Microbial fuel cells: Novel biotechnology for energy generation. Trends. Biotechnol. 2005, 23 (6), 291?298.

(29) Chen, X.; Sun, G.; Xu, M. Role of iron in azoreduction by resting cells of Shewanella decolorationis S12. J. Appl. Microbiol. 2011, 110 (2), 580?586.

(30) Wei, J. C.; Liang, P.; Cao, X. X.; Huang, X. A new insight into potential regulation on growth and power generation of Geobacter sulfurreducens in microbial fuel cells based on energy viewpoint. Environ. Sci. Technol. 2010, 44 (8), 3187?3191.

(31) Solis, M.; Solis, A.; Perez, H. I.; Manjarrez, N.; Flores, M. Microbial decolouration of azo dyes: A review. Process. Biochem. 2012, 47 (12), 1723?1748.

(32) Hong, Y. G.; Guo, J.; Xu, Z. C.; Mo, C. Y.; Xu, M. Y.; Sun, G. P. Reduction and partial degradation mechanisms of naphthylaminesulfonic azo dye amaranth by Shewanella decolordtionis S12. Appl. Microbial. Biotechnol. 2007, 75 (3), 647?654.

(33) Li, S. L.; Freguia, S.; Liu, S. M.; Cheng, S. S.; Tsujimura, S.; Shirai, O.; Kano, K. Effects of oxygen on Shewanella decolorationis NTOU1 electron transfer to carbon-felt electrodes. Biosens. Bioelectron. 2010, 25 (12), 2651?2656.

(34) Yang, Y.; Sun, G.; Guo, J.; Xu, M. Differential biofilms characteristics of Shewanella decolorationis microbial fuel cells under open and closed circuit conditions. Bioresour. Technol. 2011, 102 (14), 7093?7098.

(35) Picioreanu, C.; van Loosdrecht, M. C.; Curtis, T. P.; Scott, K. Model based evaluation of the effect of pH and electrode geometry on microbial fuel cell performance. Bioelectrochemistry 2010, 78 (1), 8?24.

(36) Franks, A. E.; Nevin, K. P.; Jia, H. F.; Izallalen, M.; Woodard, T. L.; Lovley, D. R. Novel strategy for three-dimensional real-time imaging of microbial fuel cell communities: Monitoring the inhibitory effects of proton accumulation within the anode biofilm. Energy Environ. Sci. 2009, 2 (1), 113?119.

(37) Renslow, R.; Babauta, J.; Majors, P.; Beyenal, H. Diffusion in biofilms respiring on electrodes. Energy Environ. Sci. 2013, 6 (2), 595? 607.

(38) Okamoto, A.; Hashimoto, K.; Nealson, K. H.; Nakamura, R. Rate enhancement of bacterial extracellular electron transport involves bound flavin semiquinones. Proc. Natl. Acad. Sci. U.S.A. 2013, 110 (19), 7856?7861.

(39) Sayama, M.; Risgaard-Petersen, N.; Nielsen, L. P.; Fossing, H.; Christensen, P. B. Impact of bacterial NO3(?) transport on sediment biogeochemistry. Appl. Environ. Microbial. 2005, 71 (11), 7575?7.

(40) Stewart, P. S. Diffusion in biofilms. J. Bacteriol. 2003, 185 (5), 1485?1491.

(41) Nevin, K. P.; Kim, B. C.; Glaven, R. H.; Johnson, J. P.; Woodard, T. L.; Methe, B. A.; DiDonato, R. J.; Covalla, S. F.; Franks, A. E.; Liu, A.; Lovley, D. R. Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells. PloS ONE 2009, 4 (5), e5628.

(42) Virdis, B.; Read, S. T.; Rabaey, K.; Rozendal, R. A.; Yuan, Z. G.; Keller, J. Biofilm stratification during simultaneous nitrification and denitrification (SND) at a biocathode. Bioresour. Technol. 2011, 102 (1), 334?341.

(43) Wrighton, K. C.; Thrash, J. C.; Melnyk, R. A.; Bigi, J. P.; ByrneBailey, K. G.; Remis, J. P.; Schichnes, D.; Auer, M.; Chang, C. J.; Coates, J. D. Evidence for direct electron transfer by a gram-positive bacterium isolated from a microbial fuel cell. Appl. Environ. Microbial. 2011, 77 (21), 7633?9.

(44) Liu, Y.; Bond, D. R. Long-distance electron transfer by G. sulfurreducens biofilms results in accumulation of reduced c-type cytochromes. ChemSusChem 2012, 5 (6), 1047?1053.

生物膜的呼吸系統(tǒng)和生理層次中的電子受體的依賴性——摘要、介紹

生物膜的呼吸系統(tǒng)和生理層次中的電子受體的依賴性——材料和方法

生物膜的呼吸系統(tǒng)和生理層次中的電子受體的依賴性——結(jié)果和討論

生物膜的呼吸系統(tǒng)和生理層次中的電子受體的依賴性——結(jié)論、致謝！