title: DNA gyrase genes in Mycobacterium tuberculosis: a single operon driven by multiple promoters.
abstract: The two genes encoding DNA gyrase in Mycobacterium tuberculosis are present next to each other in the genome, with gyrB upstream of gyrA. We show that the primary transcript is dicistronic. However, in addition to the principal promoter, there are multiple weaker promoters that appear to fine-tune transcription. With these and other mycobacterial promoters, we propose consensus promoter sequences for two distinct sigma factors. In addition to this, the gyr genes in M. tuberculosis, as in other species, are subject to autoregulation, albeit with slower kinetics, probably reflecting the slower metabolism of the organism.
authors.affiliation: Department of Microbiology and Cell Biology, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Shyam
authors.initials: S
authors.lastname: Unniraman
authors.forename: Monalisa
authors.initials: M
authors.lastname: Chatterji
authors.forename: Valakunja
authors.initials: V
authors.lastname: Nagaraja
mesh_terms: D001483:Base Sequence; D016384:Consensus Sequence; D027081:DNA Gyrase / Q000235:genetics* / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D009876:Operon; D011401:Promoter Regions, Genetic / Q000235:genetics* / Q000502:physiology; D012808:Sigma Factor / Q000737:chemistry / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D012808:Sigma Factor; D027081:DNA Gyrase