1nue
|
X-RAY STRUCTURE OF NM23 HUMAN NUCLEOSIDE DIPHOSPHATE KINASE B COMPLEXED WITH GDP AT 2 ANGSTROMS RESOLUTION
OverviewOverview
BACKGROUND: Nucleoside diphosphate (NDP) kinases provide precursors for, DNA and RNA synthesis. In mammals, these enzymes are also involved in cell, regulations. Human NDP kinase B, product of the human nm23-H2 gene, is, both an enzyme and a transcription factor. It activates transcription of, the c-myc oncogene independently of its catalytic function, by binding to, its promoter DNA. How do the two functions coexist? RESULTS: Recombinant, human NDP kinase B was co-crystallized with GDP. The X-ray structure was, solved at 2.0 A resolution by molecular replacement from the homologous, Drosophila Awd protein. Both enzymes are homo-hexamers with a, characteristic beta alpha beta beta alpha beta fold. GDP binds near the, active site His118. The guanine base is in a surface cleft and interacts, with the C terminus of another subunit. CONCLUSIONS: The beta alpha beta, beta alpha beta fold, also present in the 'palm' domain of Escherichia, coli DNA polymerase I and HIV reverse transcriptase, is both a, mononucleotide- and a polynucleotide-binding fold. If NDP kinase B binds, DNA in the same way as the polymerases, the enzyme must undergo a, conformation change in order to carry out gene activation.
About this StructureAbout this Structure
1NUE is a Single protein structure of sequence from Homo sapiens with MG and GDP as ligands. Active as Nucleoside-diphosphate kinase, with EC number 2.7.4.6 Full crystallographic information is available from OCA.
ReferenceReference
X-ray structure of human nucleoside diphosphate kinase B complexed with GDP at 2 A resolution., Morera S, Lacombe ML, Xu Y, LeBras G, Janin J, Structure. 1995 Dec 15;3(12):1307-14. PMID:8747457
Page seeded by OCA on Mon Nov 12 18:25:37 2007