Primary structure of inorganic polyphosphate/ATP-NAD kinase from Micrococcus flavus, and occurrence of substrate inorganic polyphosphate for the enzyme.
The gene encoding an inorganic polyphosphate/ATP-NAD kinase was cloned from Micrococcus flavus, and its primary structure was analyzed. Alignment of the primary structure with those of other characterized NAD kinases revealed candidate amino acid residues, mainly charged ones, that would be related to inorganic polyphosphate use. The alignment also showed that the primary structure found carried a protruding C-terminal polypeptide. Although the C-terminal polypeptide was demonstrated to be dispensable for the kinase activities, and was proposed to be removed in M. flavus, the entire primary structure including the C-terminal polypeptide was homologous with that of the ATP synthase beta chain. The inorganic polyphosphate used by the inorganic polyphosphate/ATP-NAD kinase as a phosphoryl donor was isolated from cells of M. flavus, suggesting that the ability of the enzyme to use inorganic polyphosphate is of physiological significance and is not an evolutionary trait alone.
Kawai
Shigeyuki
S
Department of Basic and Applied Molecular Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.
Mori
Shigetarou
S
Murata
Kousaku
K
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D003062:Codon / Q000235:genetics; D008837:Micrococcus / Q000166:cytology / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D010761:Phosphorus Radioisotopes; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D011122:Polyphosphates / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
D001426:Bacterial Proteins; D003062:Codon; D010761:Phosphorus Radioisotopes; D011122:Polyphosphates; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D017853:Phosphotransferases (Alcohol Group Acceptor); C021844:NAD kinase