Characterization of a virulence-associated and cell-wall-located DNase of Streptococcus pyogenes.

摘要: We investigated culture supernatant proteins from the M1 serotype of Streptococcus pyogenes by two-dimensional gel electrophoresis and peptide mass mapping analysis, characterized single protein spots. Among them, we analysed Spy0747 protein. This is homologous to SsnA protein, a cell-wall-located DNase expressed in suis 2. designated as SpnA. SpnA was also detected insoluble fraction whole-cell lysates using shotgun proteomic suggesting that located cell wall. glutathione S-transferase-fusion Escherichia coli. confirmed recombinant had activity dependent on Ca2+ Mg2+, like SsnA. Blood bactericidal assays mouse infection model experiments showed spnA knockout strain less virulent than parental strain, thus could play an important role virulence. Using PCR, found gene present all clinical S. strains examined. Our results, together with previous report identifying surface-associated suggest generally produced involved