The accessory Sec system (SecY2A2) in Streptococcus pneumoniae is involved in export of pneumolysin toxin, adhesion and biofilm formation.
The accessory Sec system (SecY2A2) in Streptococcus pneumoniae is involved in export of pneumolysin toxin, adhesion and biofilm formation.
复制标题
DOI：
10.1016/j.micinf.2017.04.003
复制
发表时间：
2017-07
影响因子：
5.8
通讯作者：
Jenkinson HF
中科院分区：
文献类型：
--
作者：
Bandara M;Skehel JM;Kadioglu A;Collinson I;Nobbs AH;Blocker AJ;Jenkinson HF
在肺炎链球菌TIGR4中，编码SecY2A2辅助Sec系统的基因存在于编码富含丝氨酸的重复表面蛋白PsrP的位点内。在secA2或psrP中缺失的突变株缺乏生物膜的形成，而ΔsecA2突变株与气道上皮细胞的结合减少。来自ΔsecA2突变体的细胞壁蛋白（CWP）活性降低，而来自ΔpsrP突变体的细胞壁蛋白（CWP）活性则没有降低。野生型TIGR4细胞的接触依赖性气溶素（Ply）活性比ΔsecA2突变型细胞高10倍，这表明Ply在ΔsecA2细胞表面没有活性。在ΔsecA2突变体的CWP片段中发现了Ply蛋白，但显示出异常的电泳迁移，表明蛋白修饰。蛋白质组学分析发现ΔsecA2突变体CWP片段缺乏两种糖苷酶以及其他与碳水化合物代谢有关的酶。综上所述，这些结果表明，以活性形式将Ply与糖基水解酶和粘附素一起定位到细胞壁区，需要一个功能性的辅助Sec系统。
In Streptococcus pneumoniae TIGR4, genes encoding a SecY2A2 accessory Sec system are present within a locus encoding a serine-rich repeat surface protein PsrP. Mutant strains deleted in secA2 or psrP were deficient in biofilm formation, while the ΔsecA2 mutant was reduced in binding to airway epithelial cells. Cell wall protein (CWP) fractions from the ΔsecA2 mutant, but not from the ΔpsrP mutant, were reduced in haemolytic (pneumolysin) activity. Contact-dependent pneumolysin (Ply) activity of wild type TIGR4 cells was ten-fold greater than that of ΔsecA2 mutant cells suggesting that Ply was not active at the ΔsecA2 cell surface. Ply protein was found to be present in the CWP fraction from the ΔsecA2 mutant, but showed aberrant electrophoretic migration indicative of protein modification. Proteomic analyses led to the discovery that the ΔsecA2 mutant CWP fraction was deficient in two glycosidases as well as other enzymes involved in carbohydrate metabolism. Taken collectively the results suggest that positioning of Ply into the cell wall compartment in active form, together with glycosyl hydrolases and adhesins, requires a functional accessory Sec system.
登录
查看更多内容
影响因子：
3.4
作者：
Malet JK;Cossart P;Ribet D
通讯作者：
Ribet D
影响因子：
6.7
作者：
Greene NG;Narciso AR;Filipe SR;Camilli A
通讯作者：
Camilli A
DOI：
10.1074/jbc.m116.729806
发表时间：
2016-10-07
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Bandara M;Corey RA;Martin R;Skehel JM;Blocker AJ;Jenkinson HF;Collinson I
通讯作者：
Collinson I
影响因子：
6.4
作者：
Blanchette-Cain K;Hinojosa CA;Akula Suresh Babu R;Lizcano A;Gonzalez-Juarbe N;Munoz-Almagro C;Sanchez CJ;Bergman MA;Orihuela CJ
通讯作者：
Orihuela CJ
影响因子：
3.1
作者：
Blanchette, Krystle A.;Shenoy, Anukul T.;Orihuela, Carlos J.
通讯作者：
Orihuela, Carlos J.