Functional analysis of the EsaB component of the Staphylococcus aureus Type VII secretion system.
Functional analysis of the EsaB component of the Staphylococcus aureus Type VII secretion system.
复制标题
DOI：
10.1099/mic.0.000580
复制
发表时间：
2017-12
期刊：
影响因子：
--
通讯作者：
Palmer T
中科院分区：
文献类型：
--
作者：
Casabona MG;Buchanan G;Zoltner M;Harkins CP;Holden MTG;Palmer T
VII 型分泌系统（T7SS）存在于许多细菌中，并分泌参与毒力和细菌竞争的蛋白质。在金黄色葡萄球菌中，小的类泛素 EsaB 蛋白先前被认为在 EsxC 底物的产生中具有调节作用。在这里，我们表明，在金黄色葡萄球菌 RN6390 菌株中，EsaB 不会从基因上调节任何 T7 底物或成分的产生，但对于分泌活性是必不可少的。与 EsaB 是 T7SS 的重要组成部分一致，EsaB 或 EssC 的丢失与一组常见的铁获取基因的上调有关。然而，只有在 EsaB 缺失的情况下，另一部分基因才会失调。定量蛋白质印迹表明 EsaB 在细胞中的存在水平非常低。用高度保守的苏氨酸替代丙氨酸或精氨酸会导致 EsaB 活性丧失和蛋白质不稳定。总而言之，我们的研究结果表明 EsaB 对于 RN6390 中的 T7SS 活性至关重要。
Type VII secretion systems (T7SS) are found in many bacteria and secrete proteins involved in virulence and bacterial competition. In Staphylococcus aureus the small ubiquitin-like EsaB protein has been previously implicated as having a regulatory role in the production of the EsxC substrate. Here we show that in the S. aureus RN6390 strain, EsaB does not genetically regulate production of any T7 substrates or components, but is indispensable for secretion activity. Consistent with EsaB being an essential component of the T7SS, loss of either EsaB or EssC are associated with upregulation of a common set of iron acquisition genes. However, a further subset of genes were dysregulated only in the absence of EsaB. Quantitative western blotting indicates that EsaB is present at very low levels in cells. Substitution of a highly conserved threonine for alanine or arginine resulted in a loss of EsaB activity and destabilisation of the protein. Taken together our findings show that EsaB is essential for T7SS activity in RN6390.
登录
查看更多内容
影响因子：
3.6
作者：
Kneuper H;Cao ZP;Twomey KB;Zoltner M;Jäger F;Cargill JS;Chalmers J;van der Kooi-Pol MM;van Dijl JM;Ryan RP;Hunter WN;Palmer T
通讯作者：
Palmer T
影响因子：
28.3
作者：
Beckham, Katherine S. H.;Ciccarelli, Luciano;Houben, Edith N. G.
通讯作者：
Houben, Edith N. G.
影响因子：
2.6
作者：
Corrigan, Rebecca M.;Foster, Timothy J.
通讯作者：
Foster, Timothy J.
影响因子：
82.9
作者：
Pym, AS;Brodin, P;Cole, ST
通讯作者：
Cole, ST
影响因子：
28.3
作者：
Cao Z;Casabona MG;Kneuper H;Chalmers JD;Palmer T
通讯作者：
Palmer T