title: Structural analysis of sigma E interactions with core RNA polymerase and its cognate P-hsp20 promoter of Mycobacterium tuberculosis.
abstract: Alternate sigma factor plays an important role for the survival of Mycobacterium tuberculosis in adverse environmental condition. Stress-induced sigma factors are major cause for expression of genes involved in pathogenesis, dormancy and various unusual environmental conditions. In the present work, an attempt has been made to characterize one of such M. tuberculosis (Mtb) sigma factor, SigE. The structures of Mtb-SigE and Mtb-β have been predicted using comparative modelling techniques and validated. Effort has also been implied to understand the nature of interaction of SigE with the core RNA polymerase subunits which have well identified the amino acid residues in the binding interface and prompted the fact that Mtb-β' and Mtb-β interact with domain 2 and domain 4 of Mtb-SigE, respectively. Furthermore, intermolecular docking study predicted the interface between the Mtb-SigE and its putative promoter P-hsp20. The report confers the probable amino acid residues and the nitrogenous bases involved in the recognition of P-hsp20 by the sigma factor to initiate the transcription process.
authors.affiliation: a Department of Microbiology , University of Calcutta , 35, Ballygunge Circular Road, Kolkata 700019 , India.
authors.forename: Aayatti Mallick
authors.initials: AM
authors.lastname: Gupta
authors.affiliation: a Department of Microbiology , University of Calcutta , 35, Ballygunge Circular Road, Kolkata 700019 , India.
authors.forename: Purab
authors.initials: P
authors.lastname: Pal
authors.affiliation: a Department of Microbiology , University of Calcutta , 35, Ballygunge Circular Road, Kolkata 700019 , India.
authors.forename: Sukhendu
authors.initials: S
authors.lastname: Mandal
mesh_terms: D000595:Amino Acid Sequence; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry* / Q000378:metabolism; D050886:HSP20 Heat-Shock Proteins / Q000235:genetics*; D008958:Models, Molecular; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011487:Protein Conformation; D021281:Quantitative Structure-Activity Relationship; D012808:Sigma Factor / Q000737:chemistry* / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D050886:HSP20 Heat-Shock Proteins; D012808:Sigma Factor; D012321:DNA-Directed RNA Polymerases
keywords: SigE-RNAP interaction; homology modelling; mycobacterial sigma factor; transcription; transcription regulator