The Regulatory Small RNA MarS Supports Virulence of Streptococcus pyogenes

• Published in: Scientific reports 2017-09, Vol.7 (1), p.12241-15, Article 12241
• Main Authors: Pappesch, Roberto, Warnke, Philipp, Mikkat, Stefan, Normann, Jana, Wisniewska-Kucper, Aleksandra, Huschka, Franziska, Wittmann, Maja, Khani, Afsaneh, Schwengers, Oliver, Oehmcke-Hecht, Sonja, Hain, Torsten, Kreikemeyer, Bernd, Patenge, Nadja
• Format: Article
• Language: English
• Subjects: 38; 38/70; 38/77; 5' Untranslated Regions; 631/326/41/2531; 631/337/384/521; 64; 64/60; 82; 82/58; Animal Structures - microbiology; Animal Structures - pathology; Animals; Bacterial Load; Bacterial Proteins - biosynthesis; Bacterial Proteins - genetics; Cells, Cultured; Deletion mutant; Disease Models, Animal; Electrophoretic Mobility Shift Assay; Gene Deletion; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Bacterial; Humanities and Social Sciences; Humans; Keratinocytes; Kidneys; Liver; Macrophages - immunology; Macrophages - microbiology; Mice, Inbred BALB C; multidisciplinary; Nucleic Acid Hybridization; Oxidative stress; Phagocytosis; Proteome - analysis; Proteomes; Ribonucleic acid; RNA; RNA, Small Untranslated - genetics; RNA, Small Untranslated - metabolism; Science; Science (multidisciplinary); Spleen; Streptococcal Infections - microbiology; Streptococcal Infections - pathology; Streptococcus infections; Streptococcus pyogenes; Streptococcus pyogenes - genetics; Streptococcus pyogenes - pathogenicity; Transcription; Virulence factors; Virulence Factors - biosynthesis
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-017-12507-z

Small regulatory RNAs (sRNAs) play a role in the control of bacterial virulence gene expression. In this study, we investigated an sRNA that was identified in Streptococcus pyogenes (group A Streptococcus , GAS) but is conserved throughout various streptococci. In a deletion strain, expression of mga , the gene encoding the multiple virulence gene regulator, was reduced. Accordingly, transcript and proteome analyses revealed decreased expression of several Mga-activated genes. Therefore, and because the sRNA was shown to interact with the 5′ UTR of the mga transcript in a gel-shift assay, we designated it MarS for m ga - a ctivating r egulatory s RNA. Down-regulation of important virulence factors, including the antiphagocytic M-protein, led to increased susceptibility of the deletion strain to phagocytosis and reduced adherence to human keratinocytes. In a mouse infection model, the marS deletion mutant showed reduced dissemination to the liver, kidney, and spleen. Additionally, deletion of marS led to increased tolerance towards oxidative stress. Our in vitro and in vivo results indicate a modulating effect of MarS on virulence gene expression and on the pathogenic potential of GAS.