title: Characterization of Mycobacterium tuberculosis LexA: recognition of a Cheo (Bacillus-type SOS) box.
abstract: The gene coding for the Mycobacterium tuberculosis homologue of LexA has been cloned and sequenced. Amino acids required for autocatalytic cleavage are conserved, whereas those important for specific DNA binding are not, when compared with Escherichia coli LexA. The transcriptional start site was mapped and a DNA sequence motif was identified which resembled the consensus Cheo box sequence involved in the regulation of DNA-damage-inducible genes in Bacillus subtilis. The M. tuberculosis-LexA protein was overexpressed in E. coli and purified by means of a His tag. The purified LexA was shown to bind to the Cheo box sequence found upstream of its own gene.
authors.affiliation: Division of Mycobacterial Research, National Institute for Medical Research, Mill Hill, London NW7 1AA, UK.
authors.forename: Farahnaz
authors.initials: F
authors.lastname: Movahedzadeh
authors.affiliation: Division of Mycobacterial Research, National Institute for Medical Research, Mill Hill, London NW7 1AA, UK.
authors.forename: M Joseph
authors.initials: MJ
authors.lastname: Colston
authors.affiliation: Division of Mycobacterial Research, National Institute for Medical Research, Mill Hill, London NW7 1AA, UK.
authors.forename: Elaine O
authors.initials: EO
authors.lastname: Davis
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000235:genetics*; D016415:Sequence Alignment; D017421:Sequence Analysis; D012697:Serine Endopeptidases / Q000235:genetics*; D000099160:LexA Repressor Protein
chemical_list: D001426:Bacterial Proteins; D012697:Serine Endopeptidases; D000099160:LexA Repressor Protein