NMR-STUDIES ON THE FLEXIBILITY OF NUCLEOSIDE DIPHOSPHATE KINASE

Human NDP kinase B, product of the nm23-H2 gene, binds DNA. It has bee n suggested that a helix hairpin on the protein surface, part of the n ucleotide substrate binding site, could accommodate DNA binding by swi nging away. The presence of flexible regions was therefore investigate d by H-1 NMR dynamic filtering. Although TOCSY peaks could be assigned to five residues at the N terminus of Dictyostelium NDP kinase, no fl exible region was detected in the human enzyme. These data favor the i dea that the protein offers different binding sites to mono- and polyn ucleotides. (C) 1997 Wiley-Liss, Inc.