Activating Compound | Comment | Organism | Structure |
---|---|---|---|
L-arginine | the enzyme is kinetically cooperative and the commonly detected hyperbolic behavior results from binding of L-arginine as a typical allosteric activator | [Bacillus] caldovelox |
Protein Variants | Comment | Organism |
---|---|---|
D199A | in contrast with the Michaelis-Menten kinetics exhibited by the wild-type enzyme, the mutant enzyme exhibits positive cooperativity with respect to L-arginine. Mutation has no effect on the hexameric structure of the enzyme | [Bacillus] caldovelox |
D199N | in contrast with the Michaelis-Menten kinetics exhibited by the wild-type enzyme, the mutant enzyme exhibits positive cooperativity with respect to L-arginine. Mutation has no effect on the hexameric structure of the enzyme | [Bacillus] caldovelox |
E256A | in contrast with the Michaelis-Menten kinetics exhibited by the wild-type enzyme, the mutant enzyme exhibits positive cooperativity with respect to L-arginine. Mutation has no effect on the hexameric structure of the enzyme | [Bacillus] caldovelox |
E256A/E278A | sigmoidal kinetics | [Bacillus] caldovelox |
E256Q | in contrast with the Michaelis-Menten kinetics exhibited by the wild-type enzyme, the mutant enzyme exhibits positive cooperativity with respect to L-arginine. Mutation has no effect on the hexameric structure of the enzyme | [Bacillus] caldovelox |
E278A | the mutation compromises interactions at the trimer/trimer interface and yields trimeric species (MW 100000 Da) exhibiting hyperbolic kinetics that changed to sigmoidal by the additional E256A mutation | [Bacillus] caldovelox |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
3.4 | - |
L-arginine | pH 9.5, 55°C, wild-type enzyme | [Bacillus] caldovelox | |
5 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E278A | [Bacillus] caldovelox | |
6.3 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256A | [Bacillus] caldovelox | |
6.5 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme D199N | [Bacillus] caldovelox | |
7.2 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256A/E278A | [Bacillus] caldovelox | |
9.1 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256Q | [Bacillus] caldovelox | |
9.8 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme D199A | [Bacillus] caldovelox |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mn2+ | all recombinant variants are active even in the absence of added Mn2+ but express about2.5-fold increased activity in the presence of 2 mM Mn2+. After extensive dialysis against 25 mM EDTA, they became totally dependent on added Mn2+ for catalytic activity. The manganese-reactivation of all fully inactivated species followed hyperbolic kinetics | [Bacillus] caldovelox |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
195000 | - |
gel filtration | [Bacillus] caldovelox |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-arginine + H2O | [Bacillus] caldovelox | - |
L-ornithine + urea | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
[Bacillus] caldovelox | P53608 | - |
- |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-arginine + H2O | - |
[Bacillus] caldovelox | L-ornithine + urea | - |
? |
Subunits | Comment | Organism |
---|---|---|
hexamer | 6 * 32000, SDS-PAGE | [Bacillus] caldovelox |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
300 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256A | [Bacillus] caldovelox | |
300 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256A/E278A | [Bacillus] caldovelox | |
400 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme D199N | [Bacillus] caldovelox | |
400 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256Q | [Bacillus] caldovelox | |
500 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme D199A | [Bacillus] caldovelox | |
700 | - |
L-arginine | pH 9.5, 55°C, wild-type enzyme | [Bacillus] caldovelox | |
750 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E278A | [Bacillus] caldovelox |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
44 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256Q | [Bacillus] caldovelox | |
47.8 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme E256A | [Bacillus] caldovelox | |
51.1 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme D199A | [Bacillus] caldovelox | |
61.6 | - |
L-arginine | pH 9.5, 55°C, mutant enzyme D199N | [Bacillus] caldovelox | |
206.8 | - |
L-arginine | pH 9.5, 55°C, wild-type enzyme | [Bacillus] caldovelox |