Frequency of the erythrogenic toxin B and C genes (speB and speC) among clinical isolates of group A streptococci.

AUTOR(ES)

Yu, C E

RESUMO

DNA probes corresponding to the internal region of the erythrogenic toxin B and C genes, speB and speC, were used in hybridization studies with clinical isolates of Streptococcus pyogenes to determine the frequency of occurrence of these genes in a large population of group A streptococci. More than 500 strains from different geographical locations throughout the world were used in this study. The results from colony-lift hybridization experiments indicated that the frequency of occurrence of each toxin gene among all of these strains was 100% for speB and 50% for speC. Division of these strains into subgroups of general group A strains and strains associated with scarlet fever or rheumatic fever resulted in a frequency of occurrence of speC of about 50% for all subgroups. The speC gene was found to be more frequently associated with serotype M2, M4, and M6 strains and less frequently associated with serotype M1, M3, and M49 strains. The results from a similar study with the speA gene have been previously reported (C.-E. Yu and J.J. Ferretti, Infect. Immun. 57:3715-3719, 1989).

Documentos Relacionados

• Locations of the speA, speB, speC, and metK genes on the physical map of Escherichia coli.
• Inactivation of the streptococcal erythrogenic toxin B gene (speB) in Streptococcus pyogenes.
• Detection and nucleotide sequence analysis of the speC gene in Swedish clinical group A streptococcal isolates.
• Reciprocal, Temporal Expression of SpeA and SpeB by Invasive M1T1 Group A Streptococcal Isolates In Vivo
• Antibiotic resistance and penicillin tolerance in clinical isolates of group B streptococci.