Cloned (Comment) | Organism |
---|---|
tHisH and tHisF from Thermotoga maritima are produced in Escherichia coli | Thermotoga maritima |
Protein Variants | Comment | Organism |
---|---|---|
C9A | mutant of subunit HisF. The catalytic efficiencies kcat/Km of both isolated and complexed tHisF_C9A are not significantly different from wild-type tHisF, ruling out any central catalytic role for the replaced residue | Thermotoga maritima |
D130N | mutant of subunit HisF. The catalytic efficiency kcat/Km for 5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide is decreased by approximately 5 orders of magnitude | Thermotoga maritima |
D176N | mutant of subunit HisF. Variant tHisF_D176N shows a 40-50 fold decrease in kcat, both in isolated form and in complex with tHisH | Thermotoga maritima |
D183N | mutant of subunit HisF. The catalytic efficiencies kcat/Km of both isolated and complexed tHisF_D183N are not significantly different from wild-type tHisF, ruling out any central catalytic role for the replaced residue. Both kcat and Km are drastically impaired in the mutant enzyme | Thermotoga maritima |
D51N | mutant of subunit HisF. The catalytic efficiencies kcat/Km of both isolated and complexed tHisF_D51N are not significantly different from wild-type tHisF, ruling out any central catalytic role for the replaced residue | Thermotoga maritima |
K19S | mutant of subunit HisF. The ammonia-dependent reactions of isolated tHisF_K19S are similarly efficient as those of wild-type tHisF. In contrast, the efficiencies of the glutamine-dependent reactions of the tHisHtHisF_K19S complex are significantly impaired | Thermotoga maritima |
N103A | mutant of subunit HisF. The catalytic efficiencies kcat/Km of both isolated and complexed tHisF_N103A are not significantly different from wild-type tHisF, ruling out any central catalytic role for the replaced residue | Thermotoga maritima |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0015 | - |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide | pH 8.0, 25°C, wild-type HisH-HisF complex | Thermotoga maritima | |
0.0017 | - |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide | pH 8.5, 25°C, ammonia-dependent reaction of isolated HisF subunit, wild-type | Thermotoga maritima | |
0.32 | - |
L-glutamine | pH 8.0, 25°C, wild-type HisH-HisF complex | Thermotoga maritima | |
2.2 | - |
NH4+ | pH 8.5, 25°C, ammonia-dependent reaction of isolated HisF subunit, wild-type | Thermotoga maritima |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + L-glutamine | Thermotoga maritima | the enzyme links histidine and de novo purine biosynthesis | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + L-glutamate | - |
? | |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + L-glutamine | Thermotoga maritima ATCC 43589 | the enzyme links histidine and de novo purine biosynthesis | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + L-glutamate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Thermotoga maritima | Q9X0C6 AND Q9X0C8 | Q9X0C6: subunit HisF, Q9X0C8: subunit HisH | - |
Thermotoga maritima ATCC 43589 | Q9X0C6 AND Q9X0C8 | Q9X0C6: subunit HisF, Q9X0C8: subunit HisH | - |
Purification (Comment) | Organism |
---|---|
- |
Thermotoga maritima |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + L-glutamine | - |
Thermotoga maritima | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + L-glutamate | - |
? | |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + L-glutamine | the enzyme links histidine and de novo purine biosynthesis | Thermotoga maritima | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + L-glutamate | - |
? | |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + L-glutamine | - |
Thermotoga maritima ATCC 43589 | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + L-glutamate | - |
? | |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + L-glutamine | the enzyme links histidine and de novo purine biosynthesis | Thermotoga maritima ATCC 43589 | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + L-glutamate | - |
? | |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + NH4+ | ammonia-dependent ImGP synthase reaction of isolated HisF subunit | Thermotoga maritima | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + H2O | - |
? | |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + NH4+ | ammonia-dependent ImGP synthase reaction of isolated HisF subunit | Thermotoga maritima ATCC 43589 | 5-amino-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide + D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate + H2O | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | imidazole glycerol phosphate synthase constitutes a bienzyme complex of the glutaminase subunit HisH and the synthase subunit HisF. Isolated tHisH shows no detectable glutaminase activity but is stimulated by complex formation with tHisF to which either the product imidazole glycerol phosphate or a substrate analogue are bound | Thermotoga maritima |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.4 | - |
L-glutamine | pH 8.0, 25°C, wild-type HisH-HisF complex | Thermotoga maritima | |
0.8 | - |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide | pH 8.0, 25°C, wild-type HisH-HisF complex | Thermotoga maritima | |
2 | - |
NH4+ | pH 8.5, 25°C, ammonia-dependent reaction of isolated HisF subunit, wild-type | Thermotoga maritima | |
2.2 | - |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide | pH 8.5, 25°C, ammonia-dependent reaction of isolated HisF subunit, wild-type | Thermotoga maritima |
General Information | Comment | Organism |
---|---|---|
metabolism | the enzyme links histidine and de novo purine biosynthesis | Thermotoga maritima |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
1.4 | - |
L-glutamine | pH 8.0, 25°C, wild-type enzyme HisHF | Thermotoga maritima | |
600 | - |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide | pH 8.0, 25°C, wild-type HisH-HisF complex | Thermotoga maritima | |
900 | - |
NH4+ | pH 8.5, 25°C, ammonia-dependent reaction of isolated HisF subunit, wild-type | Thermotoga maritima | |
1300 | - |
5-[(5-phospho-1-deoxy-D-ribulos-1-ylamino)methylideneamino]-1-(5-phospho-beta-D-ribosyl)imidazole-4-carboxamide | pH 8.5, 25°C, ammonia-dependent reaction of isolated HisF subunit, wild-type | Thermotoga maritima |