結(jié)論

本研究的結(jié)果表明，當(dāng)存在一個(gè)以上的電子受體時(shí)，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(yáng)極競(jìng)爭(zhēng)電子，但脫色鏈球菌菌株S12同時(shí)與陽(yáng)極和莧菜紅呼吸。 此外，MFCs陽(yáng)極室中出現(xiàn)了空間分離的呼吸模式。 浮游細(xì)胞和外層生物膜細(xì)胞傾向于使用莧菜紅作為電子受體，而內(nèi)層生物膜細(xì)胞傾向于使用陽(yáng)極作為電子受體。 與僅用陽(yáng)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(yáng)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(shì)，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(duì)生物膜電位影響較小，但陽(yáng)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(shí)使用莧菜紅和陽(yáng)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(yáng)極競(jìng)爭(zhēng)電子，但脫色鏈球菌菌株S12同時(shí)與陽(yáng)極和莧菜紅呼吸。此外，MFCs陽(yáng)極室中出現(xiàn)了空間分離的呼吸模式。浮游細(xì)胞和外層生物膜細(xì)胞傾向于使用莧菜紅作為電子受體，而內(nèi)層生物膜細(xì)胞傾向于使用陽(yáng)極作為電子受體。與僅用陽(yáng)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(yáng)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(shì)，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(duì)生物膜電位影響較小，但陽(yáng)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(shí)使用莧菜紅和陽(yáng)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(fèi)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(xiàn)

Y.Y.，M.X.和G.S.設(shè)計(jì)了實(shí)驗(yàn)。 Y.Y.和Y.X.進(jìn)行了實(shí)驗(yàn)。 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(jìng)爭(zhēng)的經(jīng)濟(jì)利益。

致謝

我們感謝Joy D.Van Nostrand博士對(duì)語(yǔ)言修訂的熱情幫助。 本研究得到中國(guó)國(guó)家基礎(chǔ)研究計(jì)劃（973計(jì)劃）（2012CB22307）、中國(guó)廣東自然科學(xué)基金（S2013010014596）、國(guó)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(jì)區(qū)域創(chuàng)新發(fā)展示范項(xiàng)目（GD2012-D01-002）。

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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！