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Examinations of the Chemical Step in Enzyme Catalysis.

ABSTRACT: Advances in computational and experimental methods in enzymology have aided comprehension of enzyme-catalyzed chemical reactions. The main difficulty in comparing computational findings to rate measurements is that the first examines a single energy barrier, while the second frequently reflects a combination of many microscopic barriers. We present here intrinsic kinetic isotope effects and their temperature dependence as a useful experimental probe of a single chemical step in a complex kinetic cascade. Computational predictions are tested by this method for two model enzymes: dihydrofolate reductase and thymidylate synthase. The description highlights the significance of collaboration between experimentalists and theoreticians to develop a better understanding of enzyme-catalyzed chemical conversions.

SUBMITTER: Singh P

PROVIDER: S-EPMC4978192 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Examinations of the Chemical Step in Enzyme Catalysis.

Singh P P Islam Z Z Kohen A A

Methods in enzymology 20160628

Advances in computational and experimental methods in enzymology have aided comprehension of enzyme-catalyzed chemical reactions. The main difficulty in comparing computational findings to rate measurements is that the first examines a single energy barrier, while the second frequently reflects a combination of many microscopic barriers. We present here intrinsic kinetic isotope effects and their temperature dependence as a useful experimental probe of a single chemical step in a complex kinetic ...[more]

PMID: 27498642

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