X-RAY STRUCTURE OF NUCLEOSIDE DIPHOSPHATE KINASE
X-RAY STRUCTURE OF NUCLEOSIDE DIPHOSPHATE KINASE
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DOI：
10.1002/j.1460-2075.1992.tb05397.x
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发表时间：
1992-09-01
期刊：
影响因子：
11.4
通讯作者：
JANIN, J
中科院分区：
文献类型：
--
作者：
DUMAS, C;LASCU, I;JANIN, J
本文报道了盘基网柄藻（Dictyosterichdiscoideum）核苷二磷酸激酶（NDP激酶）点突变体的X射线结构，其分辨力为2.2埃。该酶是由具有新的单核苷酸肽结合折叠的相同亚基组成的六聚体。每个亚基含有一个α/β结构域，具有一个四链、反向平行的β折叠。拓扑结构不同于腺苷酸激酶，但与大肠杆菌ATCase调节亚基的变构结构域相同，其在等同位置结合单核苷酸。六聚体内NDP激酶亚基之间的二聚体接触类似于ATCase中的那些。三聚体接触涉及一个大的多肽链环，该环在高度同源的果蝇酶的K-pn突变体中具有Pro →> Ser取代位点。果蝇NDP激酶，AWD发育基因的产物，和人类酶，肿瘤发生中的nm 23基因的产物的特性，讨论了三维结构和NDP激酶与其他核苷酸结合蛋白的可能相互作用。
The X-ray structure of a point mutant of nucleoside diphosphate kinase (NDP kinase) from Dictyostelium discoideum has been determined to 2.2 angstrom resolution. The enzyme is a hexamer made of identical subunits with a novel mononucleotide binding fold. Each subunit contains an alpha/beta domain with a four stranded, antiparallel beta-sheet. The topology is different from adenylate kinase, but identical to the allosteric domain of Escherichia coli ATCase regulatory subunits, which bind mononucleotides at an equivalent position. Dimer contacts between NDP kinase subunits within the hexamer are similar to those in ATCase. Trimer contacts involve a large loop of polypeptide chain that bears the site of the Pro --> Ser substitution in Killer of prune (K-pn) mutants of the highly homologous Drosophila enzyme. Properties of Drosophila NDP kinase, the product of the awd developmental gene, and of the human enzyme, the product of the nm23 genes in tumorigenesis, are discussed in view of the three-dimensional structure and of possible interactions of NDP kinase with other nucleotide binding proteins.