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Temporally overlapped but uncoupled motions in dihydrofolate reductase catalysis.

ABSTRACT: Temporal correlations between protein motions and enzymatic reactions are often interpreted as evidence for catalytically important motions. Using dihydrofolate reductase as a model system, we show that there are many protein motions that temporally overlapped with the chemical reaction, and yet they do not exhibit the same kinetic behaviors (KIE and pH dependence) as the catalyzed chemical reaction. Thus, despite the temporal correlation, these motions are not directly coupled to the chemical transformation, and they might represent a different part of the catalytic cycle or simply be the product of the intrinsic flexibility of the protein.

SUBMITTER: Liu CT

PROVIDER: S-EPMC3779903 | biostudies-literature | 2013 Aug

REPOSITORIES: biostudies-literature

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Temporally overlapped but uncoupled motions in dihydrofolate reductase catalysis.

Liu C Tony CT Wang Lin L Goodey Nina M NM Hanoian Philip P Benkovic Stephen J SJ

Biochemistry 20130729 32

Temporal correlations between protein motions and enzymatic reactions are often interpreted as evidence for catalytically important motions. Using dihydrofolate reductase as a model system, we show that there are many protein motions that temporally overlapped with the chemical reaction, and yet they do not exhibit the same kinetic behaviors (KIE and pH dependence) as the catalyzed chemical reaction. Thus, despite the temporal correlation, these motions are not directly coupled to the chemical t ...[more]

PMID: 23883151

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