Characterization of the bacteriolytic activity of nutritionally variant streptococci

The bacteriolytic activity of nutritionally variant streptococci (NVS), fastidious microaerophilic bacteria, which are members of the genera Abiotrophia and Granulicatella, was characterized in a renaturating SDS polyacrylamide gel electrophoresis system. Bacteriolytic profiles appeared quite different for the three species of NVS examined. Granulicatella adiacens or Abiotrophia defectiva each presented at least seven lytic bands, four of which were in common, while the other three were species-specific, whereas Granulicatella elegans showed six bands, which were overlapping with the G. adiacens bands. Four lytic bands were identified for enzymatic activity; d-alanyl-l-lysine hydrolase, endo-N-acetylglucosaminidase, endoacetylmuramidase, d-glutamyl-l-lysine hydrolase and acetylmuramoyl-l-alanine amidase activities could be defined. The bacteriolytic enzymes were purified and characterized for the kinetics of production during growth, autolytic activity, temperature and pH stability.