Coordinate positive regulation of genes encoding [NiFe] hydrogenases in Methanococcus voltae

• Published in: Molecular genetics and genomics : MGG Vol. 265; no. 6; pp. 1069 - 1075
• Main Authors: Müller, S., Klein, A.
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01.08.2001
• Subjects: [NiFe] hydrogenase; Base Sequence; Binding Sites; Chromatography; Chromatography, Affinity; Cloning; DNA-Binding Proteins - genetics; DNA-Binding Proteins - isolation & purification; DNA-Binding Proteins - metabolism; Gene expression; Gene Expression Regulation, Archaeal; Gene Expression Regulation, Enzymologic; Glucuronidase - genetics; Glucuronidase - metabolism; Hydrogenase - genetics; Introns; Isoenzymes - genetics; Methanococcus - genetics; Methanococcus voltae; Microorganisms; Molecular Sequence Data; Mutagenesis; Mutagenesis, Site-Directed; Mutation; Plasmids; Proteins; Restriction Mapping; RNA polymerase; Selenium; Selenium - metabolism; Transcription factors; Transcription, Genetic
• ISSN: 1617-4615; 1617-4623
• DOI: 10.1007/s004380100504

Two transcription units encoding selenium-free [NiFe] hydrogenases in Methanococcus voltae are transcribed only upon selenium deprivation. Their products replace or complement selenocysteine-containing isoenzymes. The transcription units are linked by a 453-bp intergenic region, and are subject to both positive and negative transcriptional regulation. The mechanism of positive regulation was studied in detail. Mutations in identical 11-bp putative activator recognition sites close to each promoter showed that each site is involved in the activation of both promoters. Sequence-specific DNA-affinity chromatography yielded a 55-kDa protein which specifically recognized the 11-bp sequence. We consider this protein to be a transcriptional activator for both transcription units.