The in vitro DNA binding properties of NDP kinase are related to its oligomeric state

Abstract

Genetic and biochemical evidences suggest that the enzymatic activity of NDP kinase is necessary but not sufficient for its biological function. While the human NDPK-B binds specifically single-strand polypyrimidines sequences, the hexameric enzyme from Dictyostelium does not. We demonstrated by electrophoretic mobility shift assay and filter binding assay that a dimeric mutant from Dictyostelium binds to an oligodesoxynucleotide while the wild-type does not. These data suggest that the differences in the DNA binding properties of several eucaryotic NDP kinases might be correlated to the differences in the stability of their hexameric structure.