Reconstructing electron transfer components from an Fe(II) oxidizing bacterium
Reconstructing electron transfer components from an Fe(II) oxidizing bacterium
复制标题
DOI：
10.1099/mic.0.001240
复制
发表时间：
2022-09-01
期刊：
影响因子：
2.8
通讯作者：
Gralnick，Jeffrey A.
中科院分区：
文献类型：
--
作者：
Jain，Abhiney;Kalb，Madison J.;Gralnick，Jeffrey A.
嗜中性Fe(II)氧化菌在生物地球化学过程中起着重要的作用，在多种技术应用中也受到了重视。这些微生物被认为将其代谢与细胞外电子转移(EET)耦合起来，同时以细胞外电子供体的身份氧化Fe(II)。营养石氧化杆菌ES-1是一种淡水化学自养Fe(II)氧化细菌，对培养具有挑战性，而且在遗传上还不容易处理。对这些问题的分析。ES-1基因组预测了多种EET途径，这些途径被认为与Fe(II)氧化有关，但尚未得到证实。在这里，我们表达了两个拟议的EET通路的组件，包括MTO和Sit_0867-0870 PCC3通路。ES-1进入嗜水气单胞菌，一个已建立的EET模式生物。我们证明了来自MTO和Sit_0867-0870PCC3途径的假定的内膜和周质成分的组合在缺乏天然成分的航空单胞菌突变株中部分互补了EET活性。我们的结果为MTO和Sit_0867-0870 PCC3途径的内膜和周质组分的电子转移功能和相互作用提供了证据。基于这些发现，我们建议EET INS。滋石症ES-1可能比之前认为的更复杂，并提出了关于这些电子转移途径的方向性的问题。
Neutrophilic Fe(II) oxidizing bacteria play an important role in biogeochemical processes and have also received attention for multiple technological applications. These micro-organisms are thought to couple their metabolism with extracellular electron transfer (EET) while oxidizing Fe(II) as electron donor outside the cell.Sideroxydans lithotrophicusES-1 is a freshwater chemolithoautotrophic Fe(II) oxidizing bacterium that is challenging to culture and not yet genetically tractable. Analysis of theS. lithotrophicusES-1 genome predicts multiple EET pathways, which are proposed to be involved in Fe(II) oxidation, but not yet validated. Here we expressed components of two of the proposed EET pathways, including the Mto and Slit_0867–0870 PCC3 pathways,fromS. lithotrophicusES-1 intoAeromonas hydrophila, an established model EET organism. We demonstrate that combinations of putative inner membrane and periplasmic components from the Mto and Slit_0867–0870 PCC3 pathways partially complemented EET activity inAeromonasmutants lacking native components. Our results provide evidence for electron transfer functionality and interactions of inner membrane and periplasmic components from the Mto and Slit_0867–0870 PCC3 pathways. Based on these findings, we suggest that EET inS. lithotrophicusES-1 could be more complicated than previously considered and raises questions regarding directionality of these electron transfer pathways.