Equilibrium of sortase A dimerization on Staphylococcus aureus cell surface mediates its cell wall sorting activity
Equilibrium of sortase A dimerization on Staphylococcus aureus cell surface mediates its cell wall sorting activity
复制标题
金黄色葡萄球菌细胞表面分选酶A二聚化介导其细胞壁分选活性
DOI：
10.1177/1535370215592122
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发表时间：
2016-01
影响因子：
3.2
通讯作者：
Zhiwen Zhang
中科院分区：
文献类型：
--
作者：
Jie Zhu;Liang Xiang;Faqin Jiang;Zhiwen Zhang
金黄色葡萄球菌分选酶 A (SrtA) 转肽酶是革兰氏阳性菌中一种治疗上重要的膜结合酶，它将共价附着在生物体肽聚糖细胞壁上的细胞表面蛋白组织起来。在这里，我们报告了 SrtA 在细胞膜上高选择性同二聚化的直接观察。为了解决二聚化对酶功能的生物学意义，进行定点诱变以产生 SrtA 突变体，该突变体以单体形式存在于细胞膜上。我们观察到表达单体SrtA突变体的金黄色葡萄球菌细胞中粘附蛋白的细胞表面展示比表达野生型酶的细胞更突出。还进行了基于细胞的侵袭测定，以评估野生型 SrtA 及其单体突变体的活性。我们的数据表明，以单体形式表达 SrtA 的金黄色葡萄球菌细胞比以二聚体-单体平衡表达野生型 SrtA 的金黄色葡萄球菌细胞更有效地侵入宿主哺乳动物细胞。结果表明，在细胞表面展示感染毒力因子方面，单体形式的 SrtA 比二聚形式的酶更活跃。这是首次研究 SrtA 的寡聚化及其在细胞膜上的相关生物学功能。 SrtA 二聚化的研究对于理解其在细胞水平上的催化机制以及新型抗感染药物的开发具有重要意义。
Staphylococcus aureus sortase A (SrtA) transpeptidase is a therapeutically important membrane-bound enzyme in Gram-positive bacteria, which organizes the covalently attached cell surface proteins on the peptidoglycan cell wall of the organism. Here, we report the direct observation of the highly selective homo-dimerization of SrtA on the cell membrane. To address the biological significance of the dimerization towards enzyme function, site-directed mutagenesis was performed to generate a SrtA mutant, which exists as monomer on the cell membrane. We observed that the cell surface display of adhesive proteins in S. aureus cells expressing monomeric SrtA mutant is more prominent than the cells expressing the wild-type enzyme. A cell-based invasion assay was also performed to evaluate the activities of wild-type SrtA and its monomeric mutant as well. Our data demonstrated that S. aureus cells expressing SrtA in monomeric form invade host mammalian cells more efficiently than those expressing wild-type SrtA in dimer-monomer equilibrium. The results suggested that the monomeric form of SrtA is more active than the dimeric form of the enzyme in terms of cell surface display of virulence factors for infection. This is the first study to present the oligomerization of SrtA and its related biological function on the cell membrane. Study of SrtA dimerization has implications for understanding its catalytic mechanism at the cellular level as well as the development of novel anti-infective agents.
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位点特异性蛋白质与遗传掺入3,4-二羟基L-苯丙氨酸的交联。
影响因子：
3.2
作者：
Umeda, Aiko;Thibodeaux, Gabrielle Nina;Zhu, Jie;Lee, YungAh;Zhang, Zhiwen Jonathan
通讯作者：
Zhang, Zhiwen Jonathan
DOI：
10.1074/jbc.273.44.29143
发表时间：
1998-10
期刊：
The Journal of Biological Chemistry
影响因子：
--
作者：
H. Ton-That;H. Labischinski;B. Berger-Bächi;O. Schneewind
通讯作者：
H. Ton-That;H. Labischinski;B. Berger-Bächi;O. Schneewind
DOI：
10.1056/nejm199812313392716
发表时间：
1998-12
期刊：
The New England journal of medicine
影响因子：
--
作者：
S. Blot;K. Vandewoude;F. Colardyn
通讯作者：
S. Blot;K. Vandewoude;F. Colardyn
影响因子：
3.1
作者：
Ahmed, S;Meghji, S;Nair, SP
通讯作者：
Nair, SP
影响因子：
3.2
作者：
Aiko Umeda;G. N. Thibodeaux;Jie-ping Zhu;YungAh Lee;Z. Zhang
通讯作者：
Aiko Umeda;G. N. Thibodeaux;Jie-ping Zhu;YungAh Lee;Z. Zhang