PMID:12446641

From EcoliWiki
Jump to navigation Jump to search
Citation

Kurnasov, OV, Polanuyer, BM, Ananta, S, Sloutsky, R, Tam, A, Gerdes, SY and Osterman, AL (2002) Ribosylnicotinamide kinase domain of NadR protein: identification and implications in NAD biosynthesis. J. Bacteriol. 184:6906-17

Abstract

NAD is an indispensable redox cofactor in all organisms. Most of the genes required for NAD biosynthesis in various species are known. Ribosylnicotinamide kinase (RNK) was among the few unknown (missing) genes involved with NAD salvage and recycling pathways. Using a comparative genome analysis involving reconstruction of NAD metabolism from genomic data, we predicted and experimentally verified that bacterial RNK is encoded within the 3' region of the nadR gene. Based on these results and previous data, the full-size multifunctional NadR protein (as in Escherichia coli) is composed of (i) an N-terminal DNA-binding domain involved in the transcriptional regulation of NAD biosynthesis, (ii) a central nicotinamide mononucleotide adenylyltransferase (NMNAT) domain, and (iii) a C-terminal RNK domain. The RNK and NMNAT enzymatic activities of recombinant NadR proteins from Salmonella enterica serovar Typhimurium and Haemophilus influenzae were quantitatively characterized. We propose a model for the complete salvage pathway from exogenous N-ribosylnicotinamide to NAD which involves the concerted action of the PnuC transporter and NRK, followed by the NMNAT activity of the NadR protein. Both the pnuC and nadR genes were proven to be essential for the growth and survival of H. influenzae, thus implicating them as potential narrow-spectrum drug targets.

Links

PubMed PMC135457

Keywords

Adenosine Triphosphate/metabolism; Amino Acid Sequence; Bacterial Proteins/physiology; Binding Sites; Chromatography, High Pressure Liquid; Molecular Sequence Data; NAD/biosynthesis; Nicotinamide-Nucleotide Adenylyltransferase/physiology; Phosphorylation; Phosphotransferases (Alcohol Group Acceptor)/physiology; Repressor Proteins/chemistry; Repressor Proteins/genetics; Repressor Proteins/physiology

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.