Abstract
Mandelate racemase catalyzes the interconversion of the enantiomers of mandelic acid. The enzyme binds the intermediate analogues (R)- and (S)-alpha-fluorobenzylphosphonate, and alpha,alpha-difluorobenzylphosphonate with 100-2500 times less affinity than it exhibits for (R,S)-alpha-hydroxybenzylphosphonate at pH 7.5. This apparent low affinity, relative to that of alpha-hydroxybenzylphosphonate, arises from the altered pKa values of the alpha-fluorobenzylphosphonates. For example, (S)-alpha-fluorobenzylphosphonate is bound with the same affinity as the substrate at pH 7.5, but this affinity is increased approximately 6-fold at pH 6.3.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Benzyl Compounds / chemistry
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Benzyl Compounds / pharmacology
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Enzyme Inhibitors / chemistry
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Enzyme Inhibitors / pharmacology
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Hydrocarbons, Fluorinated / chemistry*
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Hydrocarbons, Fluorinated / pharmacology*
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Hydrogen Bonding
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Hydrogen-Ion Concentration
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Kinetics
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Magnesium / chemistry
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Mandelic Acids / metabolism
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Organophosphonates / chemistry*
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Organophosphonates / pharmacology*
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Pseudomonas putida / enzymology
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Racemases and Epimerases / antagonists & inhibitors*
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Racemases and Epimerases / metabolism
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Recombinant Proteins / antagonists & inhibitors
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Recombinant Proteins / metabolism
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Stereoisomerism
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Structure-Activity Relationship
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Thermodynamics
Substances
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Benzyl Compounds
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Enzyme Inhibitors
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Hydrocarbons, Fluorinated
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Mandelic Acids
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Organophosphonates
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Recombinant Proteins
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Racemases and Epimerases
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mandelate racemase
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Magnesium
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mandelic acid