Characterization of theStreptomyces coelicolor A3(2)wblE gene, encoding a homologue of the sporulation transcription factor

• Published in: Folia microbiologica Vol. 48; no. 4; pp. 489 - 495
• Main Authors: Homerová, D, Ševčíková, J, Kormanec, J
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.07.2003
• Subjects: Actinorhodin; Antibiotics; Conserved sequence; Developmental stages; Differentiation; Gene expression; Gene mapping; Genes; Genetics; Homology; Mutants; Nuclease; Open reading frames; Sequence analysis; Similarity; Sporulation; Transcription factors; Undecylprodigiosin
• ISSN: 0015-5632; 1874-9356
• DOI: 10.1007/BF02931330

The gene corresponding to the recently identifiedwhiB-paralogous genewblE inS. coelicolor was found after sequencing the downstream region of the stress-response sporulation-specific σ-factor gene,sigH, inS. coelicolor A3(2). Sequence analysis has revealed an ORF exhibiting high similarity to sporulation transcription factors WhiB and WhiD. A stable null mutant of thewblE gene was obtained by integrative transformation,via double cross-over. Disruption of theS. coelicolor wblE gene appeared to have no obvious effect on growth, morphology, differentiation, and production of the pigmented antibiotics actinorhodin and undecylprodigiosin. Expression of thewblE gene was investigated during differentiation by S1 nuclease mapping, using RNA prepared fromS. coelicolor A3(2) and its isogenicsigF andsigH mutants grown to various developmental stages. A single promoter was identified upstream of thewblE coding region. ThewblEp promoter was induced at the beginning of aerial mycelium formation and its activity decreased later in differentiation. No differences in expression of thewblEp promoter were detected inS. coelicolor A3(2) mutants insigF andsigH genes for sporulation-specific σ factors. Sequence of thewblEp promoter showed partial similarity to the consensus sequence of the extracytoplasmic σ factors.