The Aerial Mycelium-Defective Phenotype of Streptomyces Griseus Resulting From A-factor Deficiency Is Suppressed by a Ser/Thr Kinase of S. Coelicolor A3(2)

Gene. 1996 Feb 22;169(1):91-5. doi: 10.1016/0378-1119(95)00771-7.


A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) is essential for aerial mycelium formation and streptomycin (Sm) production in Streptomyces griseus. A protein Ser/Thr kinase (AfsK), the product of the Streptomyces coelicolor A3(2) afsK gene, controlling secondary metabolism in this strain, reversed the aerial mycelium-negative phenotype of an A-factor-deficient mutant strain, S. griseus HH1, and induced sporulation without affecting A-factor productivity or Sm production. A mutant AfsK protein lacking kinase activity failed to induce aerial mycelium formation which indicates the importance of the kinase activity for suppression in S. griseus. These data suggest that a Ser/Thr kinase functionally similar to S. coelicolor A3(2) AfsK plays a regulatory role in aerial mycelium formation in S. griseus, either as a member in the A-factor regulatory network or independently of this network.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4-Butyrolactone / analogs & derivatives
  • 4-Butyrolactone / metabolism
  • Carbazoles / pharmacology
  • Cell Differentiation
  • Enzyme Inhibitors / pharmacology
  • Genes, Suppressor
  • Indole Alkaloids
  • Protein Kinase C / antagonists & inhibitors
  • Protein-Serine-Threonine Kinases / metabolism*
  • Restriction Mapping
  • Spores, Bacterial / cytology
  • Streptomyces / enzymology*
  • Streptomyces griseus / cytology
  • Streptomyces griseus / enzymology*


  • Carbazoles
  • Enzyme Inhibitors
  • Indole Alkaloids
  • A-factor (Streptomyces)
  • staurosporine aglycone
  • Protein-Serine-Threonine Kinases
  • Protein Kinase C
  • 4-Butyrolactone