Factors contributing to the biofilm-deficient phenotype of Staphylococcus aureus sarA mutants.
Factors contributing to the biofilm-deficient phenotype of Staphylococcus aureus sarA mutants.
复制标题
有助于金黄色葡萄球菌Sara突变体的生物膜缺陷表型的因素。
DOI：
10.1371/journal.pone.0003361
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发表时间：
2008
期刊：
影响因子：
3.7
通讯作者：
Smeltzer, Mark S.
中科院分区：
文献类型：
--
作者：
Tsang, Laura H.;Cassat, James E.;Shaw, Lindsey N.;Beenken, Karen E.;Smeltzer, Mark S.
金黄色葡萄球菌中sarA的突变导致形成生物膜的能力降低，但其机制基础仍然未知。先前的转录谱分析实验确定了一些基因，这些基因在生物膜和sarA突变体中差异表达。这包括参与耐酸性和产生溶核和蛋白水解外酶的基因。在此基础上，我们在S.金黄色葡萄球菌临床分离株UAMS-1及其同基因sarA突变体，并评估对生物膜形成的影响。由于alsSD的表达在生物膜中增加，但在sarA突变体中减少，我们还产生了允许alsSD在sarA突变体中表达的质粒构建体。alsSD的突变限制了生物膜的形成，但没有达到用相应的sarA突变体观察到的程度，并且alsSD表达的恢复没有恢复形成生物膜的能力。与此相反，sarA和nuc的伴随突变显着增强生物膜形成的sarA突变体相比。尽管sspA的突变对sarA突变体形成生物膜的能力没有显著影响，但显示出抑制多种细胞外蛋白酶的产生而不抑制生长的蛋白酶抑制剂（E-64、1-10-菲咯啉和二氯异香豆素）的组合也显示出增强sarA突变体形成生物膜的能力。只有当同时使用所有三种抑制剂时，这种效果才明显。这表明sarA突变体形成生物膜的能力降低涉及所有三类细胞外蛋白酶（丝氨酸、半胱氨酸和金属蛋白酶）。包括蛋白酶抑制剂也增强了生物膜形成的sarA/nuc突变体，与突变nuc和添加蛋白酶抑制剂的组合效应，导致生物膜形成的水平与接近的UAMS-1亲本菌株的sarA突变体。这些结果表明，sarA突变体不能抑制细胞外核酸酶和多种蛋白酶的产生，具有独立但累积的效应，对S. aureus sarA突变体。
Mutation of sarA in Staphylococcus aureus results in a reduced capacity to form a biofilm, but the mechanistic basis for this remains unknown. Previous transcriptional profiling experiments identified a number of genes that are differentially expressed both in a biofilm and in a sarA mutant. This included genes involved in acid tolerance and the production of nucleolytic and proteolytic exoenzymes. Based on this we generated mutations in alsSD, nuc and sspA in the S. aureus clinical isolate UAMS-1 and its isogenic sarA mutant and assessed the impact on biofilm formation. Because expression of alsSD was increased in a biofilm but decreased in a sarA mutant, we also generated a plasmid construct that allowed expression of alsSD in a sarA mutant. Mutation of alsSD limited biofilm formation, but not to the degree observed with the corresponding sarA mutant, and restoration of alsSD expression did not restore the ability to form a biofilm. In contrast, concomitant mutation of sarA and nuc significantly enhanced biofilm formation by comparison to the sarA mutant. Although mutation of sspA had no significant impact on the ability of a sarA mutant to form a biofilm, a combination of protease inhibitors (E-64, 1-10-phenanthroline, and dichloroisocoumarin) that was shown to inhibit the production of multiple extracellular proteases without inhibiting growth was also shown to enhance the ability of a sarA mutant to form a biofilm. This effect was evident only when all three inhibitors were used concurrently. This suggests that the reduced capacity of a sarA mutant to form a biofilm involves extracellular proteases of all three classes (serine, cysteine and metalloproteases). Inclusion of protease inhibitors also enhanced biofilm formation in a sarA/nuc mutant, with the combined effect of mutating nuc and adding protease inhibitors resulting in a level of biofilm formation with the sarA mutant that approached that of the UAMS-1 parent strain. These results demonstrate that the inability of a sarA mutant to repress production of extracellular nuclease and multiple proteases have independent but cumulative effects that make a significant contribution to the biofilm-deficient phenotype of an S. aureus sarA mutant.
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影响因子：
3.1
作者：
Beenken, KE;Blevins, JS;Smeltzer, MS
通讯作者：
Smeltzer, MS
影响因子：
3.1
作者：
Cramton, SE;Gerke, C;Götz, F
通讯作者：
Götz, F
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3.1
作者：
Karlsson, A;Saravia-Otten, P;Arvidson, S
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Arvidson, S
影响因子：
9.4
作者：
Fitzpatrick, F;Humphreys, H;O'Gara, JP
通讯作者：
O'Gara, JP
影响因子：
4.4
作者：
Izano, Era A.;Amarante, Matthew A.;Kaplan, Jeffrey B.
通讯作者：
Kaplan, Jeffrey B.