Protein Variants | Comment | Organism |
---|---|---|
C109/C116 | no measurable catalytic activity, not capable of binding Zn2+ | Methanococcus vannielii |
C109A | no measurable catalytic activity, not capable of binding Zn2+ | Methanococcus vannielii |
C116A | no measurable catalytic activity, still capable of binding Zn2+ | Methanococcus vannielii |
C93A | no measurable catalytic activity | Methanococcus vannielii |
D92E | 180fold loss in catalytic efficiency (kcat/Km), decrease in Zn2+ content | Methanococcus vannielii |
D94A | no measurable catalytic activity, decrease in Zn2+ content | Methanococcus vannielii |
D94E | 2300fold decrease in activity, decrease in Zn2+ content | Methanococcus vannielii |
H110A | 500fold decrease in activity, no decrease in Zn2+ content | Methanococcus vannielii |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
5,5'-dithiobis(2-nitrobenzoic acid) | compromises the Zn2+ binding properties of the protein inducing loss of up to 90% of the metal. The enzyme is protected from inactivation by inclusion of the substrate N1-(5'-phosphoribosyl)adenosine 5'-monophosphate, while Mg2+, a metal required for catalytic activity, enhanced the rate of inactivation | Methanococcus vannielii | |
methyl methane thiosulfonate | compromises the Zn2+ binding properties of the protein inducing loss of up to 90% of the metal | Methanococcus vannielii |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.18 | - |
1-(5-phospho-beta-D-ribosyl)-AMP | mutant enzyme D94E, pH and temperature not specified in the publication | Methanococcus vannielii | |
0.83 | - |
1-(5-phospho-beta-D-ribosyl)-AMP | mutant enzyme H110A, pH and temperature not specified in the publication | Methanococcus vannielii | |
2.3 | - |
1-(5-phospho-beta-D-ribosyl)-AMP | mutant enzyme D92E, pH and temperature not specified in the publication | Methanococcus vannielii | |
4 | 10 | 1-(5-phospho-beta-D-ribosyl)-AMP | wild-type enzyme, pH and temperature not specified in the publication | Methanococcus vannielii |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required for cataltic activity. The C93 reactivity is modulated by the presence of the Zn2+ and Mg2+ and substantiates the role of this residue as a metal ligand | Methanococcus vannielii | |
Zn2+ | metalloprotein. The Zn2+ coordination site involves the three conserved cysteine residues. The C93 reactivity is modulated by the presence of the Zn2+ and Mg2+ and substantiates the role of this residue as a metal ligand | Methanococcus vannielii |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Methanococcus vannielii | Q50837 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
1-(5-phospho-beta-D-ribosyl)-AMP + H2O | - |
Methanococcus vannielii | 1-(5-phospho-beta-D-ribosyl)-5-[(5-phospho-beta-D-ribosylamino)methylideneamino]imidazole-4-carboxamide | - |
? |
Synonyms | Comment | Organism |
---|---|---|
HisI | - |
Methanococcus vannielii |
N1-(5'-phosphoribosyl) adenosine-5'-monophosphate cyclohydrolase | - |
Methanococcus vannielii |
PR-AMP cyclohydrolase | - |
Methanococcus vannielii |
General Information | Comment | Organism |
---|---|---|
physiological function | the enzyme catalyzes the third step of histidine biosynthesis | Methanococcus vannielii |