INDUCTION OF STAPHYLOCOCCAL PENICILLINASE

Abstract

Thirteen strains of penicillin resistant coagulase positive staphylococci from clinical sources show increased penicillinase activity when shaken with penicillin. Under the same conditions 7 penicillin sensitive strains show no penicillinase activity. Penicillinase activity of the routine test strain increases 15-fold under conditions precluding significant cellular multiplication. The increase in activity is most rapid and pronounced in a complex medium in the presence of air. It is inhibited by chloramphenicol, 8-hydroxy-quino-line, and comparatively high concentrations of sodium azide as well as by the replacement of the air by N. It is concluded that staphylococcal penicillinase is an inducible (adaptive) enzyme similar to that found in many spp. of the Bacillus.