Streptomyces coelicolor A3(2) produces a new yellow pigment associated with the polyketide synthase Cpk.

Streptomyces coelicolor A3(2) is an extensively studied model organism for the genetic studies of Streptomycetes - a genus known for the production of a vast number of bioactive compounds and complex regulatory networks controlling morphological differentiation and secondary metabolites production. We present the discovery of a presumptive product of the Cpk polyketide synthase. We have found that on the rich medium without glucose S. coelicolor A3(2) produces a yellow compound secreted into the medium. We have proved by complementation that production of the observed yellow pigment is dependent on cpk gene cluster previously described as cryptic type I polyketide synthase cluster. The pigment production depends on the medium composition, does not occur in the presence of glucose, and requires high density of spore suspension used for inoculation.