Deletion of the alternative sigma factor σB in Staphylococcus aureus reveals its function as a global regulator of virulence genes
Deletion of the alternative sigma factor σB in Staphylococcus aureus reveals its function as a global regulator of virulence genes
复制标题
DOI：
10.1128/jb.180.18.4814-4820.1998
复制
发表时间：
1998-09-01
影响因子：
3.2
通讯作者：
Fuchs, T
中科院分区：
文献类型：
--
作者：
Kullik, I;Giachino, P;Fuchs, T
在三种遗传上不同的金黄色葡萄球菌菌株中构建sigB操纵子的缺失，并分析所得突变体的表型。与相应的温和型菌株相比，三角洲sigB突变体表现出减少色素沉着，加速沉降，并在稳定生长期过氧化氢的敏感性增加。Delta sigB突变体中缺失的细胞质蛋白被鉴定为碱性休克蛋白23，Delta sigB突变体之一中以更高水平分泌的细胞外蛋白被鉴定为葡萄球菌热核酸酶。有趣的是，大多数sigB缺失表型仅见于金黄色葡萄球菌COL和纽曼中，而不在8325中，发现其在调节基因rsbU中含有11-bp缺失。综上所述，我们的结果表明，σ（B）是一种全局调节因子，其调节金黄色葡萄球菌中几种毒力因子的表达，并且实验室菌株8325是σ（B）缺陷型突变体。
A deletion of the sigB operon was constructed in three genetically distinct Staphylococcus aureus strains, and the phenotypes of the resulting mutants were analyzed. Compared to the corresponding mild-type strains, the Delta sigB mutants showed reduced pigmentation, accelerated sedimentation, and increased sensitivity to hydrogen peroxide during the stationary growth phase. A cytoplasmic protein missing in the Delta sigB mutants was identified as alkaline shock protein 23, and an extracellular protein excreted at higher levels in one of the Delta sigB mutants was identified as staphylococcal thermonuclease. Interestingly, most sigB deletion phenotypes were only seen in S, aureus COL and Newman and not in 8325, which was found to contain an 11-bp deletion in the regulator gene rsbU, Taken together, our results show that sigma(B) is a global regulator which modulates the expression of several virulence factors in S, aureus and that laboratory strain 8325 is a sigma(B)-defective mutant.