RT Journal Article SR Electronic T1 The rgg Gene of Streptococcus pyogenes NZ131 Positively Influences Extracellular SPE B Production JF Infection and Immunity JO Infect. Immun. FD American Society for Microbiology SP 1715 OP 1722 VO 67 IS 4 A1 Chaussee, Michael S. A1 Ajdic, Dragana A1 Ferretti, Joseph J. YR 1999 UL http://iai.asm.org/content/67/4/1715.abstract AB Streptococcus pyogenes produces several extracellular proteins, including streptococcal erythrogenic toxin B (SPE B), also known as streptococcal pyrogenic exotoxin B and streptococcal proteinase. Several reports suggest that SPE B contributes to the virulence associated with S. pyogenes; however, little is known about its regulation. Nucleotide sequence data revealed the presence, upstream of the speB gene, of a gene, designatedrgg, that was predicted to encode a polypeptide similar to previously described positive regulatory factors. The putative Rgg polypeptide of S. pyogenes NZ131 consisted of 280 amino acids and had a predicted molecular weight of 33,246. To assess the potential role of Rgg in the production of SPE B, the rgggene was insertionally inactivated in S. pyogenes NZ131, which resulted in markedly decreased SPE B production, as determined both by immunoblotting and caseinolytic activity on agar plates. However, the production of other extracellular products, including streptolysin O, streptokinase, and DNase, was not affected. Complementation of the rgg mutant with an intactrgg gene copy in S. pyogenes NZ131 could restore SPE B production and confirmed that the rgg gene product is involved in the production of SPE B.