nicotinamide riboside kinase 1; NRK 1; NmR-K 1; nicotinic acid riboside kinase 1; ribosylnicotinamide kinase 1; RNK 1; ribosylnicotinic acid kinase 1 (NRK1, NMRK1, C9orf95)

Function

• catalyzes phosphorylation of nicotinamide riboside & nicotinic acid riboside to form nicotinamide mononucleotide & nicotinic acid mononucleotide
• also phosphorylates the antitumor drugs tiazofurin & 3-deazaguanosine
• cofactor biosynthesis; NAD+ biosynthesis

ATP + N-ribosylnicotinamide = ADP + nicotinamide ribonucleotide

Kinetic parameters:

• KM=0.088 mM for nicotinamide riboside (ATP as cosubstrate)
• KM=0.068 mM for nicotinamide riboside (GTP as cosubstrate)
• KM=0.27 mM for tiazofurin (ATP as cosubstrate)
• KM=0.051 mM for nicotinic acid riboside (ATP as cosubstrate)
• KM=17 mM for uridine (ATP as cosubstrate)
• pH dependence: optimum pH is 6.5-9

Structure

• monomer
• belongs to the uridine kinase family, NRK subfamily

Alternative splicing

named isoforms=2

More general terms

• kinase or ATP-phosphotransferase

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=54981
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:54981
• OMIM: https://mirror.omim.org/entry/608704
• UniProt: http://www.uniprot.org/uniprot/Q9NWW6.html