Effect of iron limitation on the production of Streptolysin S (SLS) of Streptococcus pyogenes Group A

Abstract

The effect of iron on the growth of Streptococcus pyogenes Group A and its influence on Streptolysisn
S (SLS) production was investigated. Two strains of S. pyogenes used in this study C203S and 55903 M
were grown in iron-restricted medium. The iron chelator, (Ethylenediamindi- (o- hydroxyphenyl-acetic
acid) (EDDA) was added at a concentration giving a 10-fold molar excess over Fe. Successful growth of
strains of S. pyogenes was obtained suggesting no absolute requirement for iron in the growth and the
yield of SLS was not affected by the concentration of iron in the growth medium.