SUMMARY: Extracellular penicillinase produced by the growth of five different strains of the genus Bacillus in casein hydrolysate is rapidly inactivated at 100°, but can be strikingly protected against such inactivation by addition of 1% gelatin or high molecular weight substances present in tryptic digest and meat infusion broth.
HenryR. J.,
HousewrightR. D.1947; Studies on penicillinase. II. Mano- metric method of assaying penicillinase and penicillin, kinetics of the penicillin- penicillinase reaction and the effects of inhibitors on penicillinase. J. biol. Chem 167:559
WrightH. D.1933; The importance of adequate reduction of peptone in the preparation of media for the pneumococcus and other organisms. J. Path. Bact 37:257