Transduction of the genetic determinant for streptolysin S in group A streptococci

Abstract

The genetic determinant for streptolysin S production (SLS+) was successfully transduced to two naturally occurring nonhemolytic strains of group A streptococci (Streptococcus pyogenes), an M-type 18 strain associated with an outbreak of rheumatic fever and an M-negative variant of a type 49 strain isolated from a skin lesion. Attempts to transduce this determinant to a nonhemolytic M-type 68 strain and a nonhemolytic T-type 12 strain were not successful. Transduction was accomplished with a double temperature-sensitive mutant bacteriophage. Cellular antigenic characters and the phage sensitivity of the transductants remained unaltered. The donor strain also transduced streptomycin resistance well when the nonhemolytic type 49 strain was used as a recipient. There was no evidence of cotransduction of the determinants for streptolysin S and streptomycin resistance.