title: Crystal structure of a conserved hypothetical protein from Escherichia coli.
abstract: The crystal structure of a conserved hypothetical protein from Escherichia coli has been determined using X-ray crystallography. The protein belongs to the Cluster of Orthologous Group COG1553 (National Center for Biotechnology Information database, NLM, NIH), for which there was no structural information available until now. Structural homology search with DALI algorism indicated that this protein has a new fold with no obvious similarity to those of other proteins with known three-dimensional structures. The protein quaternary structure consists of a dimer of trimers, which makes a characteristic cylinder shape. There is a large closed cavity with approximate dimensions of 16 A x 16 A x 20 A in the center of the hexameric structure. Six putative active sites are positioned along the equatorial surface of the hexamer. There are several highly conserved residues including two possible functional cysteines in the putative active site. The possible molecular function of the protein is discussed.
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720-5230, USA.
authors.forename: Dong Hae
authors.initials: DH
authors.lastname: Shin
authors.forename: Hisao
authors.initials: H
authors.lastname: Yokota
authors.forename: Rosalind
authors.initials: R
authors.lastname: Kim
authors.forename: Sung-Hou
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D017124:Conserved Sequence; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D029968:Escherichia coli Proteins