Protein Variants | Comment | Organism |
---|---|---|
H297N | site-directed mutagenesis, analysis of ligand binding, kinetics | Pseudomonas putida |
K166C | site-directed mutagenesis, analysis of ligand binding, kinetics | Pseudomonas putida |
K166M | site-directed mutagenesis, analysis of ligand binding, kinetics | Pseudomonas putida |
K166M/H297N | site-directed mutagenesis, analysis of ligand binding, kinetics | Pseudomonas putida |
additional information | Comparison of the binding affinities of the mutant variants with the intermediate/transition state analogues benzohydroxamate and cyclohexanecarbohydroxamate reveals that cationPi/N-Pi interactions between His297 and the hydroxamate/hydroximate moiety and the phenyl ring of benzohydroxamate contribute approximately 0.26 and 0.91 kcal/mol to binding, respectively, while interactions with Lys166 contribute approximately 1.74 and 1.74 kcal/mol, respectively. Lys166 contributes over 2.93 kcal/mol to the binding of (R)-atrolactate, and His297 contributes 2.46 kcal/mol to the binding of (S)-atrolactate | Pseudomonas putida |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
benzohydroxamate | BzH, the enzyme binds the intermediate/transition state analogue inhibitor in an entropy-driven process, consistent with an increased number of hydrophobic interactions, additional specific interactions contribute to binding, detailed kinetics and binding analysis, overview | Pseudomonas putida |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Pseudomonas putida | P11444 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
(S)-mandelate = (R)-mandelate | the enzyme utilizes a two-base mechanism with Lys166 and His297 acting as Broensted acid and base catalysts, respectively, in the R -> S reaction direction. In the S -> R reaction direction, their roles are reversed | Pseudomonas putida |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
(S)-atrolactate | - |
Pseudomonas putida | (R)-atrolactate | - |
r | |
(S)-mandelate | - |
Pseudomonas putida | (R)-mandelate | - |
r |
General Information | Comment | Organism |
---|---|---|
additional information | role for the Broensted acid-base catalysts of mandelate racemase in transition state stabilization. Enzyme-catalyzed abstraction of an alpha-proton from a carbon acid substrate with a high pKa. Residues Lys166 and His297 play dual roles in catalysis: they act as Broensted acid-base catalysts, and they stabilize both the enolate moiety and phenyl ring of the altered substrate in the transition state | Pseudomonas putida |
physiological function | mandelate racemase catalyzes the interconversion of the enantiomers of mandelate | Pseudomonas putida |