The < i > Staphylococcus aureus < /i > CamS lipoprotein is a repressor of toxin production that shapes host-pathogen interaction

by Katrin Schilcher, Morgan M. Severn, Christian Jenul, Young-Saeng C. Avina, Rebecca A. Keogh, Alexander R. Horswill Lipoproteins of the opportunistic pathogenStaphylococcus aureus play a crucial role in various cellular processes and host interactions. Consisting of a protein and a lipid moiety, they support nutrient acquisition and anchor the protein to the bacterial membrane. Recently, we identified several processed and secreted small linear peptides that derive from the secretion signal sequence ofS.aureus lipoproteins. Here, we show, for the first time, that the protein moiety of theS.aureus lipoprotein CamS has a biological role that is distinct from its associated linear peptidestaph-cAM373. The small peptide was shown to be involved in interspecies horizontal gene transfer, the primary mechanism for the dissemination of antibiotic resistance among bacteria. We provide evidence that the CamS protein moiety is a potent repressor of cytotoxins, such as α-toxin and leukocidins. The CamS-mediated suppression of toxin transcription was reflected by altered disease severity in in vivo infection models involving skin and soft tissue, as well as bloodstream infections. Collectively, we have uncovered the role of the protein moiety of the staphylococcal lipoprotein CamS as a previously uncharacterized repressor ofS.aureus toxin production, which consequently regulates virulence and disease outcomes. Notably, thecamS gene is conserved inS.aureus, and we also demonstrated the...
Source: PLoS Biology: Archived Table of Contents - Category: Biology Authors: Source Type: research