Electron flow and biofilms
Electron flow and biofilms
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DOI：
10.1557/mrs.2011.69
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发表时间：
2011-05-01
期刊：
影响因子：
5
通讯作者：
Finkel, Steven E.
中科院分区：
文献类型：
--
作者：
Nealson, Kenneth H.;Finkel, Steven E.
生活在表面附着生物膜群落中的细菌必须维持电化学梯度以支持基本的细胞功能，包括化学渗透运输和三磷酸腺苷合成。其核心是维持流向终端电子受体的电子流。这些受体可以是可溶的无机和有机分子，如氧、硝酸盐、硫酸盐、二甲基亚砜或富马酸盐，或固体金属氧化物，如Fe（III）和Mn（IV）氧化物。当电子转移到固体底物时，它们可能(1)通过外膜细胞色素直接携带到受体，(2)由电子穿梭分子携带，(3)沿着导电蛋白质纳米线转移，或(4)通过其他细胞外基质传导。无论电子受体是什么，在实验室中，细菌生物膜经常是在惰性表面生长时进行研究的，这些表面不能进行电子转移。然而，在自然环境中，以及许多工业和生物技术环境中，生物膜生长在电活性表面上。在这篇综述中，我们提出研究氧化还原活性表面上的细菌生物膜对于工业过程的发展，如微生物燃料电池和废水处理系统，以及我们对这些微生物群落如何影响全球营养循环，其他地球生物学过程，甚至人类疾病的理解都是重要的。
Bacteria living in surface-attached biofilm communities must maintain electrochemical gradients to support basic cellular functions, including chemo-osmotic transport and adenosine triphosphate synthesis. Central to this is the maintenance of electron flow to terminal electron acceptors. These acceptors can be soluble inorganic and organic molecules, such as oxygen, nitrate, sulfate, dimethyl sulfoxide, or fumarate, or solid metal oxides, such as Fe(III) and Mn(IV) oxides. When electrons are transferred to a solid substrate, they may be (1) carried directly to the acceptor via outer membrane cytochromes, (2) carried by electron shuttle molecules, (3) transferred along conductive protein nanowires, or (4) conducted through other extracellular matrices. No matter what the electron acceptor is, in the laboratory, bacterial biofilms are frequently studied while growing on inert surfaces, incapable of electron transfer. However, in natural environments, as well as many industrial and biotechnology settings, biofilms grow on electrically active surfaces. In this review, we propose that the study of bacterial biofilms on redox-active surfaces is important both for the development of industrial processes, such as microbial fuel cells and wastewater treatment systems, as well as for our understanding of how these communities of microbes affect global nutrient cycling, other geobiological processes, and even human disease.