<jats:p> <jats:bold>The <jats:italic>phsA</jats:italic> gene encodes phenoxazinone synthase (PHS), which catalyses the penultimate step in the pathway for actinomycin biosynthesis in <jats:italic>Streptomyces antibioticus</jats:italic>. The <jats:italic>phsA</jats:italic> promoter strikingly resembles a putative <jats:italic>Streptomyces</jats:italic>σ<jats:sup>E</jats:sup> cognate promoter, and purified Eσ<jats:sup>E</jats:sup> holoenzyme transcribed the <jats:italic>phsA</jats:italic> promoter <jats:italic>in vitro</jats:italic>. However, the <jats:italic>phsA</jats:italic> promoter was still active in an <jats:italic>S. antibioticus</jats:italic><jats:italic>sigE</jats:italic> null mutant and the level of PHS activity was unaffected. Despite this, disruption of <jats:italic>sigE</jats:italic> blocked actinomycin production completely. The loss of actinomycin production correlated with a 10‐fold decrease in the activity of actinomycin synthetase I, the enzyme which catalyses the activation of the precursor of the actinomycin chromophore.</jats:bold>