Inorganic Polyphosphate/ATP-NAD kinase of Micrococcus flavus and Mycobacterium tuberculosis H37Rv.

Abstract

An enzyme with both inorganic polyphosphate [poly(P)]- and ATP-dependent NAD kinase activities was isolated from Micrococcus flavus. The enzyme was a dimer consisting of 34 kDa subunits, and was named poly(P)/ATP-NAD kinase. Internal amino acid sequences of the enzyme showed homologies with some function-unknown proteins released on the GenBank database. Among such proteins, hypothetical Rv1695 protein (Accession No. Z98268-16), which was encoded by a gene named "Rv1695" on genomic DNA of Mycobacterium tuberculosis H37Rv, was proposed to be poly(P)-dependent NAD kinase. By cloning and expression in Escherichia coli, Rv1695 was shown to encode poly(P)/ATP-NAD kinase and named ppnk. The ppnk product, recombinant-poly(P)/ATP-NAD kinase (Ppnk) was purified and characterized. The enzyme was a tetramaer consisting of 35 kDa subunits when expressed in E. coli. Poly(P)/ATP-NAD kinases of M. flavus and Ppnk of M. tuberculosis H37Rv specifically and completely phosphorylated NAD by utilizing commercially available poly(P)s and nucleoside triphosphates as phosphoryl donors.

• Authors: S Kawai, S Mori, T Mukai, S Suzuki, T Yamada, W Hashimoto, K Murata
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 276 Issue 1 Pg. 57-63 (Sep 16 2000) ISSN: 0006-291X [Print] United States
• PMID: 11006082 (Publication Type: Journal Article)
• Copyright: Copyright 2000 Academic Press.

Chemical References

• Bacterial Proteins
• Polyphosphates
• Phosphotransferases (Alcohol Group Acceptor)
• NAD kinase

Topics

• Amino Acid Sequence
• Bacterial Proteins (genetics, metabolism)
• Micrococcus (enzymology)
• Molecular Sequence Data
• Mycobacterium tuberculosis (enzymology)
• Phosphotransferases (Alcohol Group Acceptor) (genetics, isolation & purification, metabolism)
• Polyphosphates