Consideration of cysteine protease activity for serological M-typing of clinical Streptococcus pyogenes isolates.
Clinical isolates of Streptococcus pyogenes were classified by serological typing of their surface M protein. Non-M typeable strains with the emm1 gene were characterized as the degradation of M protein caused by overproduction of the extracellular cysteine protease, SpeB. These events are dependent on the growth phase. M protein produced prior to expression of SpeB is degraded in the stationary phase when the active form of SpeB is detected. The proteolytic degradation of M protein should be considered for precise M typing analysis.
Morita
Masatomo
M
Department of Bacteriology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan.
Ikebe
Tadayoshi
T
Watanabe
Haruo
H
D000942:Antigens, Bacterial / Q000235:genetics / Q000302:isolation & purification*; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000302:isolation & purification*; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000235:genetics / Q000302:isolation & purification*; D003546:Cysteine Endopeptidases / Q000032:analysis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D012703:Serotyping; D013297:Streptococcus pyogenes / Q000201:enzymology* / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D014774:Virulence
D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; C014689:streptococcal M protein; D003546:Cysteine Endopeptidases; C042477:streptopain