Substrate Proteins Take Shape at an Improved Bacterial Translocon.
Substrate Proteins Take Shape at an Improved Bacterial Translocon.
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底物蛋白在改进的细菌转运中成形。
DOI：
10.1128/jb.00618-18
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发表时间：
2019
影响因子：
3.2
通讯作者：
Oliver,Donald
中科院分区：
文献类型：
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作者：
Oliver,Donald
Sec依赖性细菌蛋白转运的表征通常依赖于包含在大肠杆菌倒置内膜囊泡的一部分中的anin vitroprotein易位系统，或者最近，主要使用单一底物（proOmpA）将纯化的SecYEG translocons重构成脂质体。发表在这期杂志上的一篇论文（P. Bariya和L. Randall，J Bacteriol 201：e00493-18，2019，https：//doi.org/10.1128/jb.00493-18）发现，在SecYEG蛋白脂质体重建过程中包含SecA蛋白显著提高了活性translocons的数量。在此讨论了SecA膜整合特性可能产生的实验有用和有趣的结果。此外，9种不同底物的限速运输步骤的测定暗示了所观察到的速率常数差异中信号肽远端的成熟区域，表明需要响应蛋白质序列和结构差异的更细致入微的运输模型。
Characterization of Sec-dependent bacterial protein transport has often relied on anin vitroprotein translocation system comprised in part of Escherichia coli inverted inner membrane vesicles or, more recently, purified SecYEG translocons reconstituted into liposomes using mostly a single substrate (proOmpA). A paper published in this issue (P. Bariya and L. Randall, J Bacteriol 201:e00493-18, 2019, https://doi.org/10.1128/jb.00493-18) finds that inclusion of SecA protein during SecYEG proteoliposome reconstitution dramatically improves the number of active translocons. This experimentally useful and intriguing result that may arise from SecA membrane integration properties is discussed here. Furthermore, determination of the rate-limiting transport step for nine different substrates implicates the mature region distal to the signal peptide in the observed rate constant differences, indicating that more nuanced transport models that respond to differences in protein sequence and structure are needed.