ClpC affects the intracellular survival capacity of Staphylococcus aureus in non-professional phagocytic cells
ClpC affects the intracellular survival capacity of Staphylococcus aureus in non-professional phagocytic cells
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DOI：
10.1038/s41598-019-52731-3
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发表时间：
2019-11-07
影响因子：
4.6
通讯作者：
Bischoff, Markus
中科院分区：
文献类型：
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作者：
Gunaratnam, Gubesh;Tuchscherr, Lorena;Bischoff, Markus
细菌在宿主细胞内的入侵和持久性要求它们适应细胞内环境中的生活。这种适应通过吞噬作用和增强的营养限制等事件诱导细菌应激。在应激过程中，细菌会合成一个称为热休克蛋白（HSP）的蛋白质家族，以促进适应和生存。先前，我们确定金黄色葡萄球菌HSP ClpC暂时改变细菌代谢和持久性。这使我们假设ClpC可能改变细胞内存活。在S.金黄色葡萄球菌菌株DSM 20231显著增强人上皮（HaCaT）和内皮（EA.hy926）细胞系中的长期细胞内存活，而不显著影响粘附或侵袭。这种表型在遗传多样的S.金黄色葡萄球菌分离株，并受到毒素/抗毒素编码位点mazEF的影响。重要的是，MazEF改变了S.金黄色葡萄球菌毒力决定因子，表明ClpC可能通过MazEF的mRNA调节活性起作用。从细胞内DSM 20231和等基因clpC突变体细胞分离的总RNA的转录分析鉴定了α-毒素（hla）、蛋白A（spa）和RNAIII转录的改变，这与ClpC负面影响S.金黄色葡萄球菌在非专职吞噬细胞，通过调制MazEF和Agr。
Invasion and persistence of bacteria within host cells requires that they adapt to life in an intracellular environment. This adaptation induces bacterial stress through events such as phagocytosis and enhanced nutrient-restriction. During stress, bacteria synthesize a family of proteins known as heat shock proteins (HSPs) to facilitate adaptation and survival. Previously, we determined the Staphylococcus aureus HSP ClpC temporally alters bacterial metabolism and persistence. This led us to hypothesize that ClpC might alter intracellular survival. Inactivation of clpC in S. aureus strain DSM20231 significantly enhanced long-term intracellular survival in human epithelial (HaCaT) and endothelial (EA.hy926) cell lines, without markedly affecting adhesion or invasion. This phenotype was similar across a genetically diverse collection of S. aureus isolates, and was influenced by the toxin/antitoxin encoding locus mazEF. Importantly, MazEF alters mRNA synthesis and/or stability of S. aureus virulence determinants, indicating ClpC may act through the mRNA modulatory activity of MazEF. Transcriptional analyses of total RNAs isolated from intracellular DSM20231 and isogenic clpC mutant cells identified alterations in transcription of a-toxin (hla), protein A (spa), and RNAIII, consistent with the hypothesis that ClpC negatively affects the intracellular survival of S. aureus in non-professional phagocytic cells, via modulation of MazEF and Agr.