Identification of promoters recognized by RNA polymerase containing Mycobacterium tuberculosis stress-response sigma factor sigma(F).
A previously optimized Escherichia coli two-plasmid system was used to identify Mycobacterium tuberculosis promoters recognized by RNA polymerase containing the M. tuberculosis stress response sigma factor sigma(F). The method allowed the identification of five new sigma(F)-dependent promoters. Transcriptional start points of the promoters were determined by high-resolution S1-nuclease mapping using RNA prepared from E. coli containing the two-plasmid system. The promoters were confirmed by an in vitro transcription assay. The Mycobacterium smegmatis and Mycobacterium tuberculosis core RNA polymerases, after complementation with sigma(F), were able to recognize all the five promoters. All the promoters contained sequences highly similar to the sequence of the previously identified M. tuberculosis sigma(F)-dependent promoter, usfXp1. Comparison of the promoters revealed a sigma(F) consensus sequence GtTtga-N(14-18)-GGGTAT. The sigma(F)-dependent promoters may govern expression of genes encoding a transcription regulator homologous to the response regulators of bacterial two-component signal transduction systems and proteins with unknown function.
Homerova
Dagmar
D
Institute of Molecular Biology, Center of Excellence for Molecular Medicine, Slovak Academy of Sciences, Dubravska cesta 21, 845 51, Bratislava, Slovak Republic.
Surdova
Katarina
K
Mikusova
Katarina
K
Kormanec
Jan
J
D012321:DNA-Directed RNA Polymerases / Q000235:genetics / Q000378:metabolism*; D005798:Genes, Bacterial / Q000235:genetics; D009169:Mycobacterium tuberculosis / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000502:physiology*; D017422:Sequence Analysis, DNA; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D012808:Sigma Factor; D012321:DNA-Directed RNA Polymerases