Geobacter sulfurreducens is a model bacterium to study the degradation of organic compounds coupled to the reduction of Fe(III). The response of G. sulfurreducens to the electron donors acetate, formate, hydrogen and a mixture of all three with Fe(III) citrate as electron acceptor was studied using comparative physiological and proteomic approaches. Variations in the supplied electron donors resulted in differential abundance of proteins involved in the citric acid cycle (CAC), gluconeogenesis, electron transport, and hydrogenases and formate dehydrogenase. Our results provided new insights into the electron donor metabolism of G. sulfurreducens. Remarkably, formate was the preferred electron donor compared to acetate, hydrogen, or acetate plus hydrogen. When hydrogen was the electron donor, formate was formed, which was associated with a high abundance of formate dehydrogenase. Notably, abundant proteins of two CO₂ fixation pathways (acetyl‐CoA pathway and the reversed oxidative CAC) corroborated chemolithoautotrophic growth of G. sulfurreducens with formate or hydrogen and CO₂, and provided novel insight into chemolithoautotrophic growth of G. sulfurreducens.

中文翻译：

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响应于乙酸根，甲酸根和/或氢作为电子供体的反应，Geobacter硫还原剂的比较蛋白质组学

还原性土壤细菌是一种模型细菌，用于研究有机化合物的降解以及Fe（III）的还原。使用比较的生理学和蛋白质组学方法研究了硫还原菌对电子给体乙酸盐，甲酸盐，氢以及三者均以柠檬酸铁（III）作为电子受体的混合物的响应。提供的电子供体的变化导致参与柠檬酸循环（CAC），糖异生，电子转运以及氢化酶和甲酸脱氢酶的蛋白质丰度差异。我们的结果提供了新的见解，G.sulfreducens的电子供体代谢。明显地，与乙酸盐，氢或乙酸盐加氢相比，甲酸是优选的电子给体。当氢是电子供体时，形成了甲酸，这与甲酸脱氢酶的高丰度有关。值得注意的是，2和CO的丰度蛋白₂固定途径（乙酰-CoA途径和反向氧化CAC）证实的化能自养增长G.硫还原用甲或氢气和CO ₂，并提供新颖的洞察的化能自养增长G.硫还原。