title: Inactivation of the cysteine protease SpeB affects hyaluronic acid capsule expression in group A streptococci.
abstract: The human pathogen Streptococcus pyogenes expresses several virulence factors that are required for the pathogens survival within the host and the concomitant development of disease. To examine the influence of one virulence factor, the extracellular cysteine protease SpeB, on the expression of other virulence factors, the speB structural gene of a serotype M3 and M49 strain was inactivated. Morphologic examination, quantification of extracellular hyaluronic acid capsule, and Northern blot analysis of the isogenic speB -mutants revealed a strain-dependent decrease of hyaluronic acid capsule production and an increase in superoxide dismutase transcription. The transcription of streptolysin O (slo), di- and oligo-peptide permease (dpp, opp), hyaluronidase (hyl), streptokinase (ska) and streptococcal pyrogenic exotoxin A (speA) was unaffected.
authors.affiliation: Department of Microbiology and Immunology, University of Miami, Miami, FL, USA. woischnik@bigfoot.com
authors.forename: M
authors.initials: M
authors.lastname: Woischnik
authors.forename: B A
authors.initials: BA
authors.lastname: Buttaro
authors.forename: A
authors.initials: A
authors.lastname: Podbielski
mesh_terms: D016667:Bacterial Capsules / Q000378:metabolism*; D001426:Bacterial Proteins; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism*; D009154:Mutation; D013297:Streptococcus pyogenes / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D006820:Hyaluronic Acid; D003546:Cysteine Endopeptidases; C042477:streptopain