Expression, Functional Characterization and X-ray Analysis of HosA, A Member of MarR Family of Transcription Regulator from Uropathogenic Escherichia coli.
Regulators belonging to multiple antibiotic resistance regulator (MarR) family are widespread in prokaryotes and are involved in regulation of genes that are responsible for virulence and pathogenicity in most of the clinically important pathogens. Here we report the transcriptional, biophysical, and X-ray analyses of homologue of SlyA (HosA), a member of MarR family that is predominantly present in the pathogenic strains of Enterobacteriaceae family. The initiation of hosA transcription was observed to occur at two independent start sites and subsequent binding study has revealed that the purified HosA interacts with its upstream region suggesting a probable autoregulation. The secondary structure analysis through circular dichroism spectroscopy demonstrated that HosA is predominantly composed of the alpha helix with higher thermal stability. To further understand the three-dimensional structure, HosA was crystallized and the crystals were diffracted to maximum of 2.9 Ǻ on exposure to X-rays. Analysis of the X-ray crystallographic data suggested a primitive space group (P 6 ? 2 2), with unit cell parameters a = b = 64.19 Å and c = 244.25 Å. The solvent content and Matthews coefficient were 41 % and 2.11 Å(3) Da(-1), respectively, which indicated the existence of two molecules of HosA in the asymmetric unit of crystal.
Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001, India.|Graduate Studies, Manipal University, Manipal, 576104, India.
Ajit
A
Roy
Centre for Chemical Biology, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500007, India.
Ravikumar
R
Reddi
Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001, India.|Graduate Studies, Manipal University, Manipal, 576104, India.
Bhavik
B
Sawhney
Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001, India.|Graduate Studies, Manipal University, Manipal, 576104, India.
Debasish Kumar
DK
Ghosh
Centre for Chemical Biology, CSIR-Indian Institute of Chemical Technology, Hyderabad, Telangana, 500007, India.
Anthony
A
Addlagatta
Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001, India. akash@cdfd.org.in.
Akash
A
Ranjan
D000595:Amino Acid Sequence; D001483:Base Sequence; D018360:Crystallography, X-Ray; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012097:Repressor Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D040681:Structural Homology, Protein; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic; D056689:Uropathogenic Escherichia coli / Q000235:genetics* / Q000378:metabolism
D029968:Escherichia coli Proteins; C498398:HosA protein, E coli; C080004:MarR protein, E coli; D011994:Recombinant Proteins; D012097:Repressor Proteins; D014157:Transcription Factors
HosA; MarR; Uropathogenic E. coli strain UMN026; X-ray crystallography; mutS-rpoS polymorphism