[Phosphohydrolase activity of Pseudomonas maltophilia]

The activity of phosphohydrolase (acid, alkaline, pyrophosphatase) was studied in two strains of Pseudomonas maltophilia: VCM-B-591 and SSE-B-715. The activity of these enzyme systems in these strains was found to be much higher than in other Pseudomonas species, viz. Ps. aeruginosa VCM-B-889, Ps. fluorescens VCM-B-553, Ps. geniculata SSE-B-338, and in E. coli B. The phosphohydrolase activity of Ps. maltophilia varied depending on the growth phase of the culture. The highest activity of acid phosphatase was registered in the middle of the exponential phase for the strain VCM-B-591 and at the beginning of this phase for the strain SSE-B-715. The activity of alkaline phosphatase was maximal, for both of the strains VCM-B-591 and SSE-B-715, at the beginning of the logarithimic growth phase. The pyrophosphatase activity of the two strains had "two peaks" at the beginning and by the end of the logarithmic phase of growth. Incubation of Ps. maltophilia cells in media without orthophosphate did not result in an increase of their phosphohydrolase activity.