Physiological factors in the regulation of alkaline phosphatase synthesis in Escherichia coli.

Alkaline phosphatase is induced in excess phosphate media by starvation either for pyrimidines or for guanine. Induction is observed both during starvation, after a lag period, and following a period of starvation. Induction is not caused by a lowering of the internal orthophosphate pool, but is linked to alterations in the levels of the nucleotide pools. Experiments with purine-requiring mutants suggest that phosphatase is induced in wild-type strains by an adenine nucleotide. Mutations in the phoR gene can produce differential responses to the different starvation regimes.