Reduced Virulence of Group A Streptococcal Tn 916 Mutants That Do Not Produce Streptolysin S
نویسندگان
چکیده
منابع مشابه
Reduced virulence of group A streptococcal Tn916 mutants that do not produce streptolysin S.
Streptolysin S (SLS) is a potent cytolytic toxin produced by nearly all group A streptococci (GAS). SLS-deficient Tn916 insertional mutants were generated from two clinical isolates of GAS, MGAS166s and T18Ps (M serotypes 1 and 18, respectively), by transposon mutagenesis using Tn916 donor strain Enterococcus faecalis CG110. Representative nonhemolytic transconjugants SBNH5 and SB30-2 each harb...
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The pathogen group A Streptococcus (GAS) produces a wide spectrum of infections including necrotizing fasciitis (NF). Streptolysin S (SLS) produces the hallmark beta-haemolytic phenotype produced by GAS. The nine-gene GAS locus (sagA-sagI) resembling a bacteriocin biosynthetic operon is necessary and sufficient for SLS production. Using precise, in-frame allelic exchange mutagenesis and single-...
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ژورنال
عنوان ژورنال: Infection and Immunity
سال: 1998
ISSN: 0019-9567,1098-5522
DOI: 10.1128/iai.66.4.1671-1679.1998