1ndp
ADENOSINE 5'-DIPHOSPHATE BINDING AND THE ACTIVE SITE OF NUCLEOSIDE DIPHOSPHATE KINASEADENOSINE 5'-DIPHOSPHATE BINDING AND THE ACTIVE SITE OF NUCLEOSIDE DIPHOSPHATE KINASE
Structural highlights
Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe X-ray structure of nucleoside diphosphate kinase (NDP kinase) from the slime mold Dictyostelium discoideum has been determined to 2.2-A resolution and refined to an R-factor of 0.19 with and without bound ADP-Mg2+. The nucleotide binds near His 122, a residue which becomes phosphorylated during the catalytic cycle. The mode of binding is different from that observed in other phosphokinases, and it involves no glycine-rich sequence. The adenine base makes only nonpolar contacts with the protein. It points outside, explaining the lack of specificity of NDP kinase toward the base. The ribose 2'- and 3'-hydroxyls and the pyrophosphate moiety are H-bonded to polar side chains. A Mg2+ ion bridges the alpha- to the beta-phosphate which approaches the imidazole group of His 122 from the N delta side. The geometry at the active site in the ADP-Mg2+ complex suggests a mechanism for catalysis whereby the gamma-phosphate of a nucleoside triphosphate can be transferred onto His 122 with a minimum of atomic motion. Adenosine 5'-diphosphate binding and the active site of nucleoside diphosphate kinase.,Morera S, Lascu I, Dumas C, LeBras G, Briozzo P, Veron M, Janin J Biochemistry. 1994 Jan 18;33(2):459-67. PMID:8286376[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
|