Restructuring catalysis in the mandelate pathway.

D C Neidhart; P L Howell; G A Petsko; J A Gerlt; J W Kozarich; V M Powers; G L Kenyon

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PubMed · 2099737

Restructuring catalysis in the mandelate pathway.

D C Neidhart·P L Howell·G A Petsko·J A Gerlt·J W Kozarich·V M Powers·G L Kenyon

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Abstract

Mandelate racemase (MR) is the first enzyme in the bacterial pathway that converts mandelic acid to benzoic acid. The mandelate pathway can utilize either enantiomer of mandelate because this enzyme interconverts them. We have solved the structure of MR at 2.5 A resolution. The enzyme is almost identical in conformation to another bacterial enzyme, muconate lactonizing enzyme (MLE). Both enzymes are TIM-barrel proteins. This result has profound implications for the evolution of enzymic function and the origin of metabolic pathways. It also implies that it should be possible to transform one enzyme into the other by site-directed mutagenesis.

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Catalysis Intramolecular Lyases Isomerases Mandelic Acids Molecular Structure Protein Conformation Racemases and Epimerases Journal Article Research Support, U.S. Gov't, P.H.S.

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D C Neidhart, P L Howell, G A Petsko, J A Gerlt, J W Kozarich, V M Powers, G L Kenyon. 1990. Restructuring catalysis in the mandelate pathway.. https://pubmed.ncbi.nlm.nih.gov/2099737/

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