Autophosphorylation of nucleoside diphosphate kinase from Myxococcus xanthus.
The nucleoside diphosphate kinase (NDP kinase) from Myxococcus xanthus has been purified to homogeneity and crystallized (J. Munoz-Dorado, M. Inouye, and S. Inouye, J. Biol. Chem. 265:2702-2706, 1990). In the presence of ATP, the NDP kinase was autophosphorylated. Phosphoamino acid analysis was carried out after acid and base hydrolyses of phosphorylated NDP kinase. It was found that the protein was phosphorylated not only at a histidine residue but also at a serine residue. Replacement of histidine 117 with a glutamine residue completely abolished the autophosphorylation and nucleotide-binding activity of the NDP kinase. Since histidine 117 is the only histidine residue that is conserved in all known NDP kinases so far characterized, the results suggest that the phosphohistidine intermediate is formed at this residue during the transphosphorylation reaction from nucleoside triphosphates to nucleoside diphosphates. Preliminary mutational analysis of putative ATP-binding sites is also presented.
Department of Biochemistry, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Rutgers, Piscataway 08854.
J
J
Muñoz-Dorado
N
N
Almaula
S
S
Inouye
M
M
Inouye
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016941:Myxococcus xanthus / Q000201:enzymology*; D009701:Nucleoside-Diphosphate Kinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009711:Nucleotides / Q000378:metabolism; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D010766:Phosphorylation; D013329:Structure-Activity Relationship
D009711:Nucleotides; D009838:Oligodeoxyribonucleotides; D000255:Adenosine Triphosphate; D009701:Nucleoside-Diphosphate Kinase