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Quantitative FRET (Förster Resonance Energy Transfer) Analysis for SENP1 Protease Kinetics Determination
Published on: February 21, 2013
Enzymatic resolution of chiral phosphinate esters
Yingchun Li1, Sarah D Aubert, Eugene G Maes
1Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
Journal of the American Chemical Society
|July 22, 2004
Summary
Bacterial phosphotriesterase enzymes show stereoselective hydrolysis of phosphinate esters. A mutant enzyme reverses wild-type selectivity, enabling chemoenzymatic synthesis of chiral phosphines and oxides.
Area of Science:
- Biochemistry
- Enzymology
- Organic Chemistry
Background:
- Bacterial phosphotriesterase (Bpt) enzymes are known for their catalytic activity.
- Stereoselective hydrolysis of phosphinate esters is a key reaction in synthetic chemistry.
Purpose of the Study:
- To investigate the stereoselectivity of wild-type and mutant bacterial phosphotriesterase on phosphinate esters.
- To explore the potential of enantiomerically pure phosphinate esters in chemoenzymatic synthesis.
Main Methods:
- Kinetic resolution of racemic phosphinate esters using wild-type and mutant Bpt.
- Preparation of enantiomerically pure phosphinate esters.
- Chemoenzymatic synthesis of P-chiral phosphines and phosphine oxides.
Main Results:
- Wild-type Bpt preferentially hydrolyzes SP-enantiomers of methyl phenyl p-X-phenylphosphinate esters.
- A specific mutant enzyme (I106T/F132A/H254G/H257W) exhibits opposite stereoselectivity, favoring RP-enantiomers.
- The mutant enzyme shows significantly enhanced hydrolysis rates for the RP-enantiomer.
Conclusions:
- Bacterial phosphotriesterase can be engineered for altered stereoselectivity in phosphinate ester hydrolysis.
- Enantiomerically pure phosphinate esters produced via enzymatic kinetic resolution are valuable precursors for chiral organophosphorus compounds.
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