Regulation of Escherichia coli K10 Aminoendopeptidase Synthesis

Publisher Website
Google Scholar
Abstract
The synthesis of alkaline phosphatase in Escherichia coil is controlled by the action of at least four genes denoted phoS, phoT, phoR and phoB. The effect of mutations in the first three of these genes on the synthesis of periplasmic aminoendopeptidase of E. coil K10 have been investigated. phoR gene product does not seem to be involved either in the constitutive or in the derepressed synthesis of this enzyme. Mutations in phoS or phoT influence the intracellular level of Pi in much the same way as depletion of Pi from the growth medium, and only as a consequence influence the synthesis of aminoendopeptidase and alkaline phosphatase. Point, amber or deletion mutations in the alkaline phosphatase structural gene do not affect aminoendopeptidase synthesis. Thus, alkaline phosphatase and ‘derepressed’ aminoendopeptidase synthesis are co‐regulated by the endogenous level of inorganic phosphate. The way by which this regulation operates is discussed.