Properties of beta-lactamase from Neisseria gonorrhoeae

Beta-lactamase activity was studied in Neisseria gonorrhoeae strains. Optimum temperature was found to be 37 degrees C. The enzyme was inactivated at temperatures higher than 60 degrees C, but remained active during storage at low temperatures (4 degrees C, -30 degrees C and -70 degrees C) for two months. Enzyme activity was observed within a pH range of 5.8-8.0, while the optimum pH was 7.0-7.2. Addition of Ni2+, Fe2+, Mn2+ and p-chloromercurybenzoate to the reaction buffer exerted a negative effect upon the activity, whereas Hg2+ and ethylene diamine tetra-acetic acid produced complete inhibition. These results would indicate the presence of -SH groups at the catalytic site of the enzyme.