Cloned (Comment) | Organism |
---|---|
His-tagged wild-type Nrk1 expression in Escherichia coli, expression of wild-type and mutant Nrk1 from the GAL1 promoter on a LEU2 plasmid in Saccharomyces cerevisiae strain BY278 | Homo sapiens |
His-tagged wild-type Nrk2 expression in Escherichia coli, expression of wild-type and mutant Nrk2 from the GAL1 promoter on a LEU2 plasmid in Saccharomyces cerevisiae strain BY278 | Homo sapiens |
Crystallization (Comment) | Organism |
---|---|
Nrk1 bound to nucleoside and nucleotide substrates and products, i.e. nicotinamide mononucleotide, ADP, tiazofurin, beta-D-ribosylnicotinate with AppNHp, and beta-D-ribosylnicotinate alone, addition of 10 mM ligand and 20 mM MgCl2, overview. Usage of different crystallization solutions depending on the ligand, containing PEG 2000 mono-methylether or PEG 3350 or PEG 4000 at 15-35%, at pH 5.0-8.0, with 0.2 M NaH2PO4, and different buffers, X-ray diffraction structure determination and analysis at 1.32-1.95 A resolution, molecular replacement | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
D35A | site-directed mutagenesis of Nrk2 | Homo sapiens |
D36A | site-directed mutagenesis of Nrk1 | Homo sapiens |
E100A | site-directed mutagenesis of Nrk2, mutant activity in ATP-dependent phosphorylation is below the level of detection | Homo sapiens |
E174R | site-directed mutagenesis of Nrk2 | Homo sapiens |
E98A | site-directed mutagenesis of Nrk1, mutant activity in ATP-dependent phosphorylation is below the level of detection | Homo sapiens |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.051 | - |
beta-D-ribosylnicotinamide | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.063 | - |
beta-D-ribosylnicotinamide | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.068 | - |
beta-D-ribosylnicotinate | Nrk1, with GTP, pH 7.5, 37°C | Homo sapiens | |
0.088 | - |
beta-D-ribosylnicotinate | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.11 | - |
tiazofurin | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.19 | - |
beta-D-ribosylnicotinate | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.27 | - |
tiazofurin | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
1.3 | - |
uridine | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
15 | - |
cytidine | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
17 | - |
uridine | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
30 | - |
cytidine | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
30 | - |
beta-D-ribosylnicotinate | Nrk2, with GTP, pH 7.5, 37°C | Homo sapiens |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Homo sapiens |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + beta-D-ribosylnicotinate | Homo sapiens | nicotinic acid riboside is a specific substrate of human Nrk enzymes | ADP + nicotinate beta-D-ribonucleotide | - |
? | |
additional information | Homo sapiens | Asp35 and Glu100 in Nrk2 are essential residues for function in vivo | ? | - |
? | |
additional information | Homo sapiens | Asp36 and Glu98 in Nrk1 are essential residues for function in vivo | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | Q9NPI5 | Nrk2; Nrk2 | - |
Homo sapiens | Q9NWW6 | Nrk1; Nrk1 | - |
Purification (Comment) | Organism |
---|---|
recombinant Nrk1 and Nrk2 from Escherichia coli by metal chelate affinity chromatography | Homo sapiens |
recombinant Nrk2 from Escherichia coli by metal chelate affinity chromatography | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + beta-D-ribosylnicotinamide | beta-D-ribosylnicotinamide is an NAD+ precursor utilized via the Nrk and Preiss-Hander pathways | Homo sapiens | ADP + nicotinamide beta-D-ribonucleotide | - |
? | |
ATP + beta-D-ribosylnicotinate | nicotinic acid riboside is a specific substrate of human Nrk enzymes | Homo sapiens | ADP + nicotinate beta-D-ribonucleotide | - |
? | |
ATP + cytidine | - |
Homo sapiens | ADP + CMP | - |
? | |
ATP + cytidine | low activity with Nrk1 | Homo sapiens | ADP + CMP | - |
? | |
ATP + nicotinamide mononucleotide | - |
Homo sapiens | ADP + nicotinamide mononucleotide phosphate | - |
? | |
ATP + tiazofurin | - |
Homo sapiens | ADP + ? | - |
? | |
ATP + tiazofurin | a relatively good Nrk1 substrate | Homo sapiens | ADP + ? | - |
? | |
ATP + uridine | - |
Homo sapiens | ADP + UMP | - |
? | |
ATP + uridine | low activity with Nrk1 | Homo sapiens | ADP + UMP | - |
? | |
GTP + beta-D-ribosylnicotinate | nicotinic acid riboside is a specific substrate of human Nrk enzymes | Homo sapiens | GDP + nicotinate beta-D-ribonucleotide | - |
? | |
additional information | Asp35 and Glu100 in Nrk2 are essential residues for function in vivo | Homo sapiens | ? | - |
? | |
additional information | Asp36 and Glu98 in Nrk1 are essential residues for function in vivo | Homo sapiens | ? | - |
? | |
additional information | substrate specificity of recombinant Nrk1 and Nrk2, overview. Classification of Nrk1 as an nicotinic acid riboside and tiazofurin:ATP or GTP kinase, Nrk1 displays a 340fold preference for nicotinic acid riboside over cytidine in the KM term and a 500fold preference over either cytidine or uridine in the kcat/KM term. Poor cytidine monophosphate-forming activity of the enzyme. Structural basis of substrate specificity, overview. Base recognition in the Nrk1 nucleoside-binding site excludes uridine but supports beta-D-ribosylnicotinamide phosphorylation | Homo sapiens | ? | - |
? | |
additional information | substrate specificity of recombinant Nrk2, overview. Classification of Nrk2 as an ATP-specific nicotinic acid riboside, tiazofurin, and uridine kinase. Poor cytidine monophosphate-forming activity of the enzyme. Structural basis of substrate specificity, overview | Homo sapiens | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | the ADP-binding site includes P-loop sequence Gly-Val-Thr-Asn-Ser-Gly-Lys-Thr, residues 10-17 | Homo sapiens |
Synonyms | Comment | Organism |
---|---|---|
nicotinamide riboside kinase | - |
Homo sapiens |
NRK1 | - |
Homo sapiens |
Nrk2 | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Homo sapiens |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.21 | - |
uridine | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.21 | - |
beta-D-ribosylnicotinamide | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.34 | - |
beta-D-ribosylnicotinate | Nrk1, with GTP, pH 7.5, 37°C | Homo sapiens | |
0.34 | - |
beta-D-ribosylnicotinamide | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.35 | - |
tiazofurin | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.48 | - |
cytidine | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.49 | - |
tiazofurin | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.6 | - |
beta-D-ribosylnicotinate | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.75 | - |
beta-D-ribosylnicotinate | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.82 | - |
cytidine | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
1.1 | - |
uridine | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
1.7 | - |
beta-D-ribosylnicotinate | Nrk2, with GTP, pH 7.5, 37°C | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Homo sapiens |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | active with Nrk1 | Homo sapiens | |
ATP | specific for Nrk2 | Homo sapiens | |
GTP | active with Nrk1 | Homo sapiens | |
additional information | GTP is not with Nrk2 | Homo sapiens |
General Information | Comment | Organism |
---|---|---|
evolution | the enzyme is structurally similar to Rossmann fold metabolite kinases | Homo sapiens |
metabolism | the enzyme is involved in the eukaryotic nicotinamide riboside kinase, Nrk, pathway, which is induced in response to nerve damage and promotes replicative life span in yeast, converts nicotinamide riboside to NAD+ by phosphorylation and adenylylation, overview. Nicotinic acid riboside is utilized in vivo by Urh1, Pnp1, and Preiss-Handler salvage | Homo sapiens |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.012 | - |
uridine | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.016 | - |
cytidine | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.055 | - |
cytidine | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
0.057 | - |
beta-D-ribosylnicotinate | Nrk2, with GTP, pH 7.5, 37°C | Homo sapiens | |
0.85 | - |
uridine | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
1.3 | - |
tiazofurin | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
3.9 | - |
beta-D-ribosylnicotinate | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
4.1 | - |
beta-D-ribosylnicotinamide | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens | |
4.5 | - |
tiazofurin | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
5 | - |
beta-D-ribosylnicotinate | Nrk1, with GTP, pH 7.5, 37°C | Homo sapiens | |
5.4 | - |
beta-D-ribosylnicotinamide | Nrk2, with ATP, pH 7.5, 37°C | Homo sapiens | |
6.8 | - |
beta-D-ribosylnicotinate | Nrk1, with ATP, pH 7.5, 37°C | Homo sapiens |