Regulation of the formation of alkaline phosphatase during neomycin biosynthesis.

The use of a washed-cell system to study the factors controlling the synthesis of alkaline phosphatase and neomycin by Streptomyces fradiae has shown that calcium and magnesium salts are stimulatory, with maximal synthesis of both achieved with a combination of these salts. Among all the carbon sources studied, only arabinose induces alkaline phosphatase synthesis, whereas glucose and other carbon sources inhibit the synthesis of the enzyme. Asparagine is a very good inducer of enzyme and neomycin synthesis, with lysine and alanine having lower stimulatory effects. The appearance of alkaline phosphatase is due to de novo protein synthesis as demonstrated by the inhibition of its synthesis in the presence of chloramphenicol. There is a good correlation between the synthesis of alkaline phosphatase and neomycin biosynthesis.