In vitro protein phosphorylation associated with cellular differentiation of Streptomyces griseus

In vitro phosphorylation reactions with crude cellular extracts revealed that phosphorylation of a 17-kDa protein is associated with the onset of aerial mycelium formation in solid culture (but not submerged spore formation in liquid culture) of Streptomyces griseus. The possible importance of the 17-kDa protein phosphorylation in cellular differentiation was further indicated by inducing aerial mycelium formation in the presence of decoyinine and in studies using certain developmental mutants (relC, afsA, and M-1). It is proposed that the 17-kDa protein may play a role in cellular differentiation of S. griseus via its phosphorylation. Received: 17 July 1997 / Accepted: 20 September 1997