Quantitative determination of catalase activity produced by Neisseria gonorrhoeae, Staphylococcus epidermidis, Neisseria meningitidis and other bacterial strains using the Catalasemeter.

The conventional catalase test only gives qualitative or semi-quantitative information of the amount of catalase activity produced. Using such a method, we have selected two strong catalase activity producers (Neisseria gonorrhoeae G-10, Staphylococcus epidermidis 66) and a weak producer (Neisseria meningitidis 34702). Quantitative determination of the catalase activity produced by these strains was done by the disk-flotation method using the Catalasemeter. The production of catalase activity in liquid culture by N. gonorrhoeae, S. epidermidis and N. meningitidis occurred mainly during the logarithmic growth phase. The maximum concentration of catalase activity found in these cultures was, for both strong producers, 160 units (U)/ml while it was around 20 U/ml for the weak producer. Some of the other bacteria tested showed high concentrations of catalase activity (130-162 U/ml) and these were: N. gonorrhoeae strain PR 77112 (penicillin resistant), Staphylococcus strain 7 (coagulase negative), Micrococcus sp. strains 2 and 42.