Cloned (Comment) | Organism |
---|---|
gene purT, recombinant enzyme expression in Escherichia coli strain TX635 from plasmid pJS455 | Escherichia coli |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | steady-state kinetics | Escherichia coli | |
0.0101 | - |
N1-(5-phospho-beta-D-ribosyl)glycinamide | recombinant enzyme, pH 8.0, 25°C | Escherichia coli | |
0.045 | - |
ATP | recombinant enzyme, pH 8.0, 25°C, with formate | Escherichia coli | |
0.319 | - |
formate | recombinant enzyme, pH 8.0, 25°C | Escherichia coli |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Co2+ | can only partially substitute for Mg2+, moderate to low activity | Escherichia coli | |
Mg2+ | required | Escherichia coli | |
Mn2+ | can only partially substitute for Mg2+, low activity | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + formate + N1-(5-phospho-beta-D-ribosyl)glycinamide | Escherichia coli | - |
ADP + phosphate + N2-formyl-N1-(5-phospho-beta-D-ribosyl)glycinamide | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | P33221 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant enzyme from Escherichia coli strain TX635 by streptomycin sulfate precipitation, dialysis, anion exchange chromatography, and ultrafiltration, followed by another different step of anion exchange chromatography, dialysis, and ultrafiltration | Escherichia coli |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
2.6 | - |
purified recombinant enzyme, pH 8.0, 25°C, with Mn2+ | Escherichia coli |
17.3 | - |
purified recombinant enzyme, pH 8.0, 25°C, with Co2+ | Escherichia coli |
52 | - |
purified recombinant enzyme, pH 8.0, 25°C, with Mg2+ | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + formate + N1-(5-phospho-beta-D-ribosyl)glycinamide | - |
Escherichia coli | ADP + phosphate + N2-formyl-N1-(5-phospho-beta-D-ribosyl)glycinamide | - |
? | |
additional information | radioactive assay monitoring the conversion of [14C]formate to fGAR or [alpha-32P] ATP to ADP. No activity with 10-formyl-5,8-dideazatetrahydrofolate (10-formyl-DDF), 5-formyl-THF, formyl-aminoimidazolecarboxamide ribonucleotide (fAICAR), formylmethionine, and formiminoglutamate as formyl donor. The enzyme shows a side reaction with ATP and acetate: cleavage of ATP in the presence of acetate to generate acetyl phosphate and ADP. The NMR study demonstrates that the purT GAR transformylase reaction proceeds through a transfer of atomic oxygen from formate to the 7-phosphoryl moiety of ATP. One interpretation is the intermediacy of formyl phosphate whose presence is also supported by the identification of acetyl phosphate as a product in the side reaction | Escherichia coli | ? | - |
- |
Subunits | Comment | Organism |
---|---|---|
? | x * 42000, SDS-PAGE | Escherichia coli |
Synonyms | Comment | Organism |
---|---|---|
GAR transformylase | - |
Escherichia coli |
non-folate glycinamide ribonucleotide transformylase | - |
Escherichia coli |
PurT | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Escherichia coli |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
37.6 | - |
formate | recombinant enzyme, pH 8.0, 25°C | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
ATP | - |
Escherichia coli | |
additional information | no activity with CTP, GTP, TTP, ITP, and aminoimidazolecarboxamide ribonucleotide triphosphate (ZTP) | Escherichia coli |
General Information | Comment | Organism |
---|---|---|
metabolism | PurT glycinamide ribonucleotide (GAR) transformylase is an alternative to the formyl-folate utilizing purN GAR transformylase. No significant homology exists between the two transformylases. But the PurT protein shows significant homology to the PurK protein, also involved in purine biosynthesis | Escherichia coli |
physiological function | PurT glycinamide ribonucleotide (GAR) transformylase is an alternative to the formyl-folate utilizing purN GAR transformylase. Biologically relevant transformation of beta-GAR into fGAR | Escherichia coli |