title: Crystal structure of an archaeal homologue of multidrug resistance repressor protein, EmrR, from hyperthermophilic archaea Sulfolobus tokodaii strain 7.
abstract: MarR family proteins, MarR, MexR, and EmrR, are known as bacterial regulators for a phenotype resistant to multiple antibiotic drugs. Genomic data have indicated the presence of bacterial-type transcriptional regulators, including MarR family proteins in archaea, though the archaeal transcription system is close to that of eukaryote. To elucidate the structural basis of the transcriptional regulation mechanism of archaeal MarR family proteins, the crystal structure of the ST1710 protein, which was identified as an archaeal EmrR homologue, StEmrR, from hyperthermophilic archaeon Sulfolobus tokodaii strain 7 was determined at 1.45-A resolution. The protein was composed of two N- and C-terminal dimerization domains, and the DNA-binding domain consisted of a winged helix motif, as in the case of bacterial MarR family proteins. Despite the relatively low overall structural similarity between StEmrR and bacterial MarR family proteins, the structure of the DNA-binding domain displayed high structural similarity. A comparison with the crystal structures of bacterial MarR family proteins revealed that structural variation was mainly due to the different orientation of the two helices at the N- and C-termini. Our results indicated that the distance between the two DNA-binding domains of MarR family proteins would be changed by the rotation of the two terminal helices to interact with the target DNA.
authors.affiliation: Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Miyazono
authors.forename: Masanari
authors.initials: M
authors.lastname: Tsujimura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kawarabayasi
authors.forename: Masaru
authors.initials: M
authors.lastname: Tanokura
mesh_terms: D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D018360:Crystallography, X-Ray; D018432:Drug Resistance, Multiple; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D016944:Sulfolobus / Q000201:enzymology*; D013696:Temperature
chemical_list: D019843:Archaeal Proteins; D012097:Repressor Proteins