title: Crystal structure of a predicted phosphoribosyltransferase (TT1426) from Thermus thermophilus HB8 at 2.01 A resolution.
abstract: TT1426, from Thermus thermophilus HB8, is a conserved hypothetical protein with a predicted phosphoribosyltransferase (PRTase) domain, as revealed by a Pfam database search. The 2.01 A crystal structure of TT1426 has been determined by the multiwavelength anomalous dispersion (MAD) method. TT1426 comprises a core domain consisting of a central five-stranded beta sheet surrounded by four alpha-helices, and a subdomain in the C terminus. The core domain structure resembles those of the type I PRTase family proteins, although a significant structural difference exists in an inserted 43-residue region. The C-terminal subdomain corresponds to the "hood," which contains a substrate-binding site in the type I PRTases. The hood structure of TT1426 differs from those of the other type I PRTases, suggesting the possibility that TT1426 binds an unknown substrate. The structure-based sequence alignment provides clues about the amino acid residues involved in catalysis and substrate binding.
authors.affiliation: RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan.
authors.forename: Mutsuko
authors.initials: M
authors.lastname: Kukimoto-Niino
authors.forename: Rie
authors.initials: R
authors.lastname: Shibata
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Murayama
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Hamana
authors.forename: Madoka
authors.initials: M
authors.lastname: Nishimoto
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Bessho
authors.forename: Takaho
authors.initials: T
authors.lastname: Terada
authors.forename: Mikako
authors.initials: M
authors.lastname: Shirouzu
authors.forename: Seiki
authors.initials: S
authors.lastname: Kuramitsu
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Yokoyama
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D018360:Crystallography, X-Ray; D008969:Molecular Sequence Data; D010430:Pentosyltransferases / Q000737:chemistry* / Q000235:genetics; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016963:Thermus thermophilus / Q000201:enzymology* / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D010430:Pentosyltransferases; C023269:uracil phosphoribosyltransferase