Crystallization (Comment) | Organism |
---|---|
free enzyme or enzyme complexed with IMP, hanging drop vapour diffusion method, 20°C, 10 mg/ml protein in 20 Tris-HCl, pH 7.4, mixed with a molar excess of IMP, 0.001 ml protein solution mixed with equal volume of reservoir solution containing 0.2 M magnesium acetate tetrahydrate, 0.1 M sodium cacodylate, pH 6.5, 12% w/v PEG 4000, or protein solution with 1 mM IMP mixed with reservoir solution containing 15% PEG 8000, 0.1 M sodium cacodylate, pH 6.5, 0.2 M magnesium acetate tetrahydrate, X-ray diffraction structure determination and analysis at 2.2-2.5 A resolution | Caldanaerobacter subterraneus subsp. tengcongensis |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
IMP | feedback inhibition, competitive versus 5-phospho-alpha-D-ribose 1-diphosphate, binding mode | Caldanaerobacter subterraneus subsp. tengcongensis |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.133 | - |
5-phospho-alpha-D-ribose 1-diphosphate | pH 7.4, 12 mM MgCl2 | Caldanaerobacter subterraneus subsp. tengcongensis | |
0.327 | - |
5-phospho-alpha-D-ribose 1-diphosphate | pH 7.4, 12 mM MgCl2, in presence of 0.05 mM IMP | Caldanaerobacter subterraneus subsp. tengcongensis |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required for binding of 5-phospho-alpha-D-ribose 1-diphosphate, binding via side chains of Glu101 and Asp102 and water molecules in the apoenzyme, binding site structure | Caldanaerobacter subterraneus subsp. tengcongensis |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
guanine + 5-phospho-alpha-D-ribose 1-diphosphate | Caldanaerobacter subterraneus subsp. tengcongensis | - |
GMP + diphosphate | - |
? | |
hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate | Caldanaerobacter subterraneus subsp. tengcongensis | - |
IMP + diphosphate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Caldanaerobacter subterraneus subsp. tengcongensis | - |
- |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
IMP + diphosphate = hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate | substrate binding structure and mechanism, a non-proline cis-peptide may be essential for activity | Caldanaerobacter subterraneus subsp. tengcongensis |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
guanine + 5-phospho-alpha-D-ribose 1-diphosphate | - |
Caldanaerobacter subterraneus subsp. tengcongensis | GMP + diphosphate | - |
? | |
hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate | - |
Caldanaerobacter subterraneus subsp. tengcongensis | IMP + diphosphate | - |
? | |
hypoxanthine + 5-phospho-alpha-D-ribose 1-diphosphate | binding mechanism and structure of IMP occupying the diphosphate site, overview | Caldanaerobacter subterraneus subsp. tengcongensis | IMP + diphosphate | - |
? | |
additional information | the conformation of the flexible loop, containing a 3-10 helix and a unique double serine repeat, is important for substrate binding and activation of the enzyme | Caldanaerobacter subterraneus subsp. tengcongensis | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
tetramer | active enzyme form, subunit A composition, overview | Caldanaerobacter subterraneus subsp. tengcongensis |
Synonyms | Comment | Organism |
---|---|---|
HGPRT | - |
Caldanaerobacter subterraneus subsp. tengcongensis |
hypoxanthine-guanine phosphoribosyltransferase | - |
Caldanaerobacter subterraneus subsp. tengcongensis |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
4.26 | - |
5-phospho-alpha-D-ribose 1-diphosphate | pH 7.4, 12 mM MgCl2 | Caldanaerobacter subterraneus subsp. tengcongensis |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.4 | - |
assay at | Caldanaerobacter subterraneus subsp. tengcongensis |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
0.045 | - |
IMP | pH 7.4, 12 mM MgCl2, versus 5-phospho-alpha-D-ribose 1-diphosphate | Caldanaerobacter subterraneus subsp. tengcongensis |