結論

本研究的結果表明，當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散了生物膜中的質子積累。 陽極呼吸生物膜的氧化還原電位呈現先降低后升高的趨勢，這與其介質占主導地位的性質相一致。 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，由于生物膜內的雙向呼吸電子轉移，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散了生物膜中的質子積累。陽極呼吸生物膜的氧化還原電位呈現先降低后升高的趨勢，這與其介質占主導地位的性質相一致。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，由于生物膜內的雙向呼吸電子轉移，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。

關聯內容

支持信息

圖S1 ? S7。 此材料可通過互聯網免費獲取，網址為 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.分析數據并撰寫手稿。

筆記

作者聲明沒有相互競爭的經濟利益。

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研究計劃（973計劃）（2012CB22307）、中國廣東自然科學基金（S2013010014596）、國家自然科學基金（51422803, 31200096）、廣東科學院優秀學者課題（RCJJ201502）的資助。 廣東省海洋經濟區域創新發展示范項目（GD2012-D01-002）。

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生物膜的呼吸系統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

生物膜的呼吸系統和生理層次中的電子受體的依賴性——結果和討論

生物膜的呼吸系統和生理層次中的電子受體的依賴性——結論、致謝！