RNA polymerase heterogeneity in Streptomyces coelicolor A3(2).

Recent genetic and biochemical experiments have revealed the existence of at least seven different sigma factors in Streptomyces coelicolor and demonstrated a role for alternative sigma factors in the control of differentiation and also in the transcription of primary metabolic genes. S. coelicolor has four genes predicted to encode sigma factors that are very closely related to the sigma 70 polypeptide of Escherichia coli.