Protein Variants | Comment | Organism |
---|---|---|
C190A | mutation in catalytic residue, no evidence of covalent binding of substrate preQ0. Mutant displays proton uptake | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
7-formyl-7-deazaguanine | carbonyl analogue of the imine intermediate, recognized by QueF as weak ligand for binding but not as substrate for reduction or oxidation | Escherichia coli |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.001 | - |
7-cyano-7-carbaguanine | below 1 microM, pH 7.5, 25°C | Escherichia coli | |
0.0078 | - |
NADPH | pH 7.5, 25°C | Escherichia coli | |
0.05 | - |
7-cyano-7-carba-2-deaminoguanine | pH 7.5, 25°C | Escherichia coli |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | - |
- |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
7-cyano-7-carba-2-deaminoguanine + 2 NADPH + 2 H+ | - |
Escherichia coli | 7-aminomethyl-7-carba-2-deaminoguanine + 2 NADP+ | - |
? | |
7-cyano-7-carbaguanine + 2 NADPH + 2 H+ | - |
Escherichia coli | 7-aminomethyl-7-carbaguanine + 2 NADP+ | - |
? | |
additional information | QueF binds substrate preQ0 in a strongly exothermic process (DeltaH 80.3 kJ/mol) whereby the thioimide adduct is formed with half-of-the-sites reactivity in the homodimeric enzyme. Both steps of preQ0 reduction involve transfer of the 4-pro-R-hydrogen from NADPH. They proceed about 4-7fold more slowly than trapping of the enzyme-bound preQ0 as covalent thioimide and are mainly rate-limiting for the enzyme's kcat | Escherichia coli | ? | - |
? |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.12 | - |
7-cyano-7-carbaguanine | pH 7.5, 25°C | Escherichia coli | |
0.14 | - |
7-cyano-7-carba-2-deaminoguanine | pH 7.5, 25°C | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NADPH | - |
Escherichia coli |