EC Number   |
Reaction  |
Reference |
|---|
    5.1.1.4 | L-proline = D-proline |
a new combined quantum mechanical and molecular mechanical (QM/MM) potential to study the reaction mechanism of proline racemase is used. Three critical points are identified: two almost isoenergetic minima (M1a and M2a), in which the enzyme is bound to L- and D-Pro, respectively, and a transition state (TSCa), unveiling a highly asynchronous concerted process |
675621 |
| 5.1.1.4 | L-proline = D-proline |
energetics of proline racemase: transition-state fractionation factors for the two protons involved in the catalytic steps |
2126 |
| 5.1.1.4 | L-proline = D-proline |
enzyme exists in two states, one of which binds and isomerizes L-Pro and the other of which binds and isomerizes D-Pro. It seems likely that the two enzyme forms differ only in the protonation states of the acidic and basic groups at the active site |
2128 |
| 5.1.1.4 | L-proline = D-proline |
fractionation factors for the essential catalytic groups in the enzyme-substrate complexes |
2129 |
| 5.1.1.4 | L-proline = D-proline |
mechanism |
2125 |
| 5.1.1.4 | L-proline = D-proline |
mechanism is best accomodated by a route that involves a transition state or unstable intermediate in which the proline carbanion is flanked by the two catalytic thiols of the enzyme |
2130 |
| 5.1.1.4 | L-proline = D-proline |
quantum mechanical and molecular mechanical study reveals two almost isoenergetic minima M1a and M2a, in which the enzyme is bound to L-proline and D-proline, respectively, and a transition state TSCa, unveiling a highly asynchronous concerted process. Residues Asn133, Asp296, and Gly301 destabilize M2a. Conversely, both Gly131and Gly303 stabilize M2a. Residues Gly131, Gly301, and Thr302 stabilize TSCa |
675621 |
| 5.1.1.4 | L-proline = D-proline |
racemization is accompanied by deuterium incorporation from the solvent into the alpha position of Pro, participation of two equivalent hydrogen acceptor sites |
2121 |
| 5.1.1.4 | L-proline = D-proline |
stepwise reaction for the interconversion of the free enzyme forms in which a proton is abstracted from a bound water molecule to give a reaction intermediate having a hydroxide ion bound to the diprotonated form of the enzyme |
2127 |
| 5.1.1.4 | L-proline = D-proline |
the substrate and product "on-off" steps are faster than the racemization step and the racemization reaction proceeds either in a concerted manner or in a stepwise fashion involving enzyme catalytic groups, e.g. thiols |
2131 |
