Expression of the gap gene encoding glyceraldehyde-3-phosphate dehydrogenase of Streptomyces aureofaciens requires GapR, a member of the AraC/xyIS family of transcriptional activators

Expression of the gap gene encoding glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of Streptomyces aureofaciens has been studied and found to require GapR. The gapR gene was constitutively expressed from one promoter during differentiation. By integrative transformation using double crossover, a stable null mutant of the gapR gene was obtained. The mutation affected growth little and differentiation not at all. Transcription of the GAPDH-encoding gap gene was substantially reduced in the S. aureofaciens (Delta)gapR null mutant, no matter what the carbon source. GapR is a member of the AraC/XyIS family of transcriptional activators.