Structure of Bacillus subtilis YXKO—A member of the UPF0031 family and a putative kinase

• Published in: Journal of structural biology 2002-09, Vol.139 (3), p.161-170
• Main Authors: Zhang, R-g., Grembecka, J., Vinokour, E., Collart, F., Dementieva, I., Minor, W., Joachimiak, A.
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphate - metabolism; Amino Acid Sequence; Animals; Bacillus subtilis - enzymology; Bacillus subtilis YXKO; Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; Binding Sites; Cloning, Molecular; Crystallography, X-Ray; Evolution, Molecular; Humans; Kinase; Metals - metabolism; Models, Molecular; Molecular Sequence Data; Molecular Weight; Phosphotransferases (Alcohol Group Acceptor) - chemistry; Phosphotransferases (Alcohol Group Acceptor) - metabolism; Protein Conformation; Sequence Homology, Amino Acid; Structural genomics; Structure-Activity Relationship; UPF0031 family
• ISSN: 1047-8477; 1095-8657
• DOI: 10.1016/S1047-8477(02)00532-4

We determined the 1.6-Å resolution crystal structure of a conserved hypothetical 29.9-kDa protein from the SIGY–CYDD intergenic region encoded by a Bacillus subtilis open reading frame in the YXKO locus. YXKO homologues are broadly distributed and are by and large described as proteins with unknown function. The YXKO protein has an α/β fold and shows high structural homology to the members of a ribokinase-like superfamily. However, YXKO is the only member of this superfamily known to form tetramers. Putative binding sites for adenosine triphosphate (ATP), a substrate, and Mg 2+-binding sites were revealed in the structure of the protein, based on high structural similarity to ATP-dependent members of the superfamily. Two adjacent monomers contribute residues to the active site. The crystal structure provides valuable information about the YXKO protein’s tertiary and quaternary structure, the biochemical function of YXKO and its homologues, and the evolution of its ribokinase-like superfamily.