title: Crystal structure of the transcriptional repressor PagR of Bacillus anthracis.
abstract: PagR is a transcriptional repressor in Bacillus anthracis that controls the chromosomal S-layer genes eag and sap, and downregulates the protective antigen pagA gene by direct binding to their promoter regions. The PagR protein sequence is similar to those of members of the ArsR repressor family involved in the repression of arsenate-resistance genes in numerous bacteria. The crystal structure of PagR was solved using multi-wavelength anomalous diffraction (MAD) techniques and was refined with 1.8 A resolution diffraction data. The PagR molecules form dimers, as observed in all SmtB/ArsR repressor family proteins. In the crystal lattice four PagR dimers pack together to form an inactive octamer. Model-building studies suggest that the dimer binds to a DNA duplex with a bend of around 4 degrees.
authors.affiliation: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Arsen
authors.initials: A
authors.lastname: Volkov
authors.affiliation: Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, 4301 W Markham St, Little Rock, AR 72205-7199, USA.
authors.forename: Vidya Harini
authors.initials: VH
authors.lastname: Veldore
authors.affiliation: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Hoch
authors.affiliation: Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, 4301 W Markham St, Little Rock, AR 72205-7199, USA.
authors.forename: Kottayil I
authors.initials: KI
authors.lastname: Varughese
mesh_terms: D000595:Amino Acid Sequence; D001408:Bacillus anthracis / Q000737:chemistry* / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D018360:Crystallography, X-Ray; D004269:DNA, Bacterial / Q000378:metabolism; D005798:Genes, Bacterial; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding / Q000235:genetics; D011487:Protein Conformation; D012097:Repressor Proteins / Q000737:chemistry* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; C548703:PagR protein, Bacillus anthracis; D012097:Repressor Proteins