A pilin chaperone required for the expression of electrically conductive Geobacter sulfurreducens pili
A pilin chaperone required for the expression of electrically conductive Geobacter sulfurreducens pili
复制标题
导电硫还原地杆菌菌毛表达所需的菌毛伴侣
DOI：
10.1111/1462-2920.14638
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发表时间：
2019-07-01
影响因子：
5.1
通讯作者：
Lovley, Derek R.
中科院分区：
文献类型：
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作者：
Liu, Xing;Zhan, Ji;Lovley, Derek R.
由于e-皮利在不同的生物地球化学过程、厌氧消化和电微生物应用中的重要作用，控制Geetum物种的导电皮利（e-皮利）表达的机制引起了人们的兴趣。我们研究了蛋白质的功能，命名为Spc（短菌毛蛋白伴侣），由紧接PilA基因下游的基因编码，PilA是组装成e-菌毛的单体。多条证据表明Spc形成与内膜相关的寡聚体。突变spc的起始密码子以阻止翻译增加了pilA的转录丰度，但大大减少了pilA的丰度，并且不再检测到e-菌毛。交联、蛋白捕获和双杂交研究表明Spc和PilA相互作用。两个网站的PilA静电相互作用与Spc被确定。结果表明，Spc是PilA稳定性所需的，然后掺入到e-菌毛，这表明Spc具有分子伴侣功能，可能是特定的组装成e-菌毛的相对较短的PilA单体。这些结果对于从（Meta）基因组数据中鉴定可能表达e-菌毛的微生物和构建表达e-菌毛的微生物菌株是重要的。
Mechanisms controlling the expression of the electrically conductive pili (e-pili) of Geobacter species are of interest because of the important role of e-pili in diverse biogeochemical processes, anaerobic digestion and electromicrobiological applications. We investigated the function of the protein, designated Spc (short pilin chaperone), encoded by the gene immediately downstream from the gene for PilA, the monomer that assembles into e-pili. Multiple lines of evidence suggest that Spc forms an oligomer that is associated with the inner membrane. Mutating the start codon of spc to prevent translation increased the transcript abundance of pilA but greatly diminished the abundance of PilA, and e-pili could no longer be detected. Cross-linking, protein capture and two-hybrid studies demonstrated that Spc and PilA interacted. Two sites in PilA for electrostatic interaction with Spc were identified. The results demonstrate that Spc is required for PilA stability prior to incorporation into e-pili, suggesting that Spc has a chaperone function that may be specific to the relatively short PilA monomers that assemble into e-pili. These results are important for identifying microorganisms likely to express e-pili from (meta)genomic data and for the construction of microbial strains expressing e-pili.