Heat-stable and heat-labile components of nonspecific acid phosphatase detected in Pseudomonas pseudomallei.

In a whole cell assay system with p-nitrophenyl phosphate as substrate, strains of Pseudomonas pseudomallei showed a two-peak pattern in pH activity curve of acid phosphatase, suggesting the presence of two enzyme components different in pH optimum (4.2 and 5.2). The component of 5.2 pH optimum was detected in the outer membrane fraction and the activity was resistant to heating at 70 C for 30 min. The other component of 4.2 pH optimum was heat-labile. No substantial difference was observed in the enzymatic activity between R and S type colonies.