Cloned (Comment) | Organism |
---|---|
nadC coding sequence cloned into the pRSETC expression vector, overexpressed in Escherichia coli nadC-deleted host strain ZB100 | Salmonella enterica subsp. enterica serovar Typhimurium |
Protein Variants | Comment | Organism |
---|---|---|
K185A | kcat value is reduced by 625fold, and binding affinity of quinolinic acid and 5-phospho-alpha-D-ribose 1-diphosphate to the enzyme decreases. Displays 83fold increase in activity toward the normally inactive quinolinic acid analogue, nicotinic acid. Displays a 300fold higher kcat/Km for nicotinic acid over the natural substrate quinolinic acid | Salmonella enterica subsp. enterica serovar Typhimurium |
additional information | mutants can use 6-aminonicotinic acid as substrate, whereas 2,4-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, nicotinamide and pyridine-4-carboxylic acid are not utilized by the mutant enzymes | Salmonella enterica subsp. enterica serovar Typhimurium |
R118A | results in 5000fold decrease in kcat value and a decrease in the binding affinity of quinolinic acid and 5-phospho-alpha-D-ribose 1-diphosphate to mutant R152A. Equimolar mixtures of mutant R118A with inactive or virtually inactive mutants produce approximately 50% of the enzymatic activity of wild-type | Salmonella enterica subsp. enterica serovar Typhimurium |
R152A | kcat value is reduced by 33fold, and binding affinity of quinolinic acid and 5-phospho-alpha-D-ribose 1-diphosphate to the enzyme decreases. Displays 116fold increase in activity toward the normally inactive quinolinic acid analogue, nicotinic acid | Salmonella enterica subsp. enterica serovar Typhimurium |
R175A | no activity | Salmonella enterica subsp. enterica serovar Typhimurium |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.027 | - |
quinolinic acid | wild-type, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.057 | - |
5-phospho-alpha-D-ribose 1-diphosphate | wild-type, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.067 | - |
quinolinic acid | mutant H188A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.136 | - |
quinolinic acid | mutant R118A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.151 | - |
nicotinic acid | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.278 | - |
quinolinic acid | mutant R152A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.547 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant H188A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.832 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant R152A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
1.478 | - |
quinolinic acid | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
2.181 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
3.138 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant R118A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Salmonella enterica subsp. enterica serovar Typhimurium | - |
- |
- |
Purification (Comment) | Organism |
---|---|
mutants purified by gel filtration, to homogeneity | Salmonella enterica subsp. enterica serovar Typhimurium |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
0.0006 | - |
wild-type with nicotinic acid at 1 mM and 2 mM 5-phospho-alpha-D-ribose 1-diphosphate | Salmonella enterica subsp. enterica serovar Typhimurium |
0.07 | - |
mutant R152A with nicotinic acid at 1 mM and 2 mM 5-phospho-alpha-D-ribose 1-diphosphate | Salmonella enterica subsp. enterica serovar Typhimurium |
0.1 | - |
mutant R152A with quinolinic acid at 1 mM and 2 mM 5-phospho-alpha-D-ribose 1-diphosphate | Salmonella enterica subsp. enterica serovar Typhimurium |
1.2 | - |
wild-type with quinolinic acid at 1 mM and 2 mM 5-phospho-alpha-D-ribose 1-diphosphate | Salmonella enterica subsp. enterica serovar Typhimurium |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
nicotinate + 5-phospho-alpha-D-ribose 1-diphosphate + ATP + H2O | - |
Salmonella enterica subsp. enterica serovar Typhimurium | beta-nicotinate D-ribonucleotide + diphosphate + ADP + phosphate | - |
? | |
quinolinic acid + 5-phospho-alpha-D-ribose 1-diphosphate | Arg175 is essential for catalysis, critical role for Lys185 in the chemistry of the QAPRTase intermediate, interfacial role for Arg118 during catalysis | Salmonella enterica subsp. enterica serovar Typhimurium | nicotinic acid mononucleotide + diphosphate + CO2 | - |
? |
Synonyms | Comment | Organism |
---|---|---|
NadC | - |
Salmonella enterica subsp. enterica serovar Typhimurium |
QAPRTase | - |
Salmonella enterica subsp. enterica serovar Typhimurium |
quinolinate phosphoribosyltransferase | - |
Salmonella enterica subsp. enterica serovar Typhimurium |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.00024 | - |
quinolinic acid | mutant R118A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.0016 | - |
quinolinic acid | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.03 | - |
quinolinic acid | mutant R152A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.048 | - |
nicotinic acid | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
1 | - |
quinolinic acid | mutant H188A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
1 | - |
quinolinic acid | wild-type, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium |
General Information | Comment | Organism |
---|---|---|
physiological function | overexpression and purification of the mutant enzymes produce 200-250 mg of protein/6 liter of culture similar to that of the wild-type enzyme | Salmonella enterica subsp. enterica serovar Typhimurium |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.000064 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant R118A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.00073 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.0011 | - |
quinolinic acid | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.0015 | - |
quinolinic acid | mutant R118A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.035 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant R152A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.1 | - |
quinolinic acid | mutant R152A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.32 | - |
nicotinic acid | mutant K185A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
1.8 | - |
5-phospho-alpha-D-ribose 1-diphosphate | mutant H188A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
16 | - |
quinolinic acid | mutant H188A, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
18 | - |
5-phospho-alpha-D-ribose 1-diphosphate | wild-type, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
37 | - |
quinolinic acid | wild-type, at 25°C | Salmonella enterica subsp. enterica serovar Typhimurium |