Abstract

Downloaded from http://jb.asm.org/ on May 14, 2021 by guest RESEARCH ARTICLE The Streptococcus pyogenes Signaling Peptide SpoV Regulates Streptolysin O and Enhances Survival in Murine Blood a a a Andrea L. Herrera, Eduardo A. Callegari, Michael S. Chaussee Division of Basic Biomedical Sciences, The Sanford School of Medicine of the University of South Dakota, Vermillion, South Dakota, USA ABSTRACT Streptococcus pyogenes (group A Streptococcus [GAS]) is a human patho- gen that causes a wide range of diseases. For successful colonization within a variety of host niches, GAS must sense and respond to environmental changes. Intercellular communication mediated by peptides is one way GAS coordinates gene expression in response to diverse environmental stressors, which enhances bacterial survival and contributes to virulence. Using peptidomics, we identified SpoV (streptococcal peptide controlling virulence) in culture supernatant fluids. SpoV is a secreted peptide encoded near the gene (slo) encoding the extracellular cholesterol-dependent cytolysin strepto- lysin O (SLO). The addition of synthetic SpoV peptide derivatives, but not control pep- tides, increased slo transcript abundance in an M49 isolate but not in an M3 isolate. Deletion of spoV decreased slo transcript abundance, extracellular SLO protein levels, and SLO-specific hemolytic activity. Complementation of the spoV mutant increased