Analysis of the virulence factors of the Streptococcus pyogenes involved in the pathogenesis of toxic shock-like syndrome of Streptococcus pyogenes infection.

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Streptococcus pyogenes secretes a variety of toxins and enzymes. These proteins, as well as surface proteins, are considered as important virulence factors. We extracted whole exoproteins of the clinical isolates of S.pyogenes from the patients who suffered toxic shock-like syndrome (TSLS) and characterized them by the two-dimensional gel electrophoresis technique. The protein expression patterns from many of the clinical isolates of the same M serotype were almost same, suggesting that the clinical features caused by them were similar. However some clinical isolates of the same M type which showed different clinical features had different protein expression patterns. We sequenced N-terminal amino acids of the proteins isolated by the two-dimensional gel electrophoresis and detected SpeB, SpeF and streptolysin O by using DNA data bank. In addition, we detected several unreported proteins which we considered as virulence factors. We have already cloned four of them. We performed the DNA sequencing, made recombinant proteins and found that they had DNase activities. We detected SpeF, which is considered to play an important roles in adult respiratory distress syndrome (ARDS), as fairly large amounts in S.pyogenes of both M1 and M3 serotypes. However, we found that SpeF had different N-terminal amino acid and different isoelectricity. We are now studying the biological significance of different SpeF spots.