Some distinctive characteristics of the alkaline phosphatase of Serratia marcescens.

A mutant strain of Serratia marcescens produces a constitutive enzyme (phosphatase F), which differs from the alkaline phosphatase of Escherichia coli in the following characteristics: one enzyme species with higher mobility on electrophoresis, less heat stability, no rapid reactivation following exposure to high hydrogen ion concentrations, no hybridization with E. coli enzyme in vitro, little activation at increased ionic strength, greater sensitivity to EDTA inhibition, and no cross reaction of rabbit anti-serum with the E. coli enzyme.