Effects of streptomycin deprivation on enzyme synthesis in streptomycin-dependent Escherichia coli.

During growth of streptomycin-dependent strains of Escherichia coli in the absence of streptomycin (deprived growth), both constitutive and inducible synthesis of beta-galactosidase were preferentially inhibited. A similar preferential inhibition of constitutive and derepressed synthesis of alkaline phosphatase was observed. Catabolite repression accounted for part, but not all, of the inhibition of the inducible beta-galactosidase synthesis. Serological experiments indicated that that part of the inhibition specificially associated with streptomycin deprivation was not a result of the production of altered beta-galactosidase. It is suggested that during deprived growth the ribosomes of streptomycin-dependent bacteria become impaired in their ability to translate certain messages.