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Fast enzyme dynamics at the active site of formate dehydrogenase.

ABSTRACT: The role of femtosecond-picosecond structural dynamics of proteins in enzyme-catalyzed reactions is a hotly debated topic. We report infrared photon echo measurement of the formate dehydrogenase-NAD+-azide ternary complex. In contrast to earlier studies of protein dynamics, the data show complete spectral diffusion on the femtosecond-picosecond time scale with no static heterogeneity. This result indicates that this transition-state analogue complex completely samples the distribution of structures that determine the distribution of azide vibrational frequencies within a few picoseconds and that there are no slower motions that perturb the H-bond network at the active site.

SUBMITTER: Bandaria JN

PROVIDER: S-EPMC2533850 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

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Fast enzyme dynamics at the active site of formate dehydrogenase.

Bandaria Jigar N JN Dutta Samrat S Hill Sarah E SE Kohen Amnon A Cheatum Christopher M CM

Journal of the American Chemical Society 20071208 1

The role of femtosecond-picosecond structural dynamics of proteins in enzyme-catalyzed reactions is a hotly debated topic. We report infrared photon echo measurement of the formate dehydrogenase-NAD+-azide ternary complex. In contrast to earlier studies of protein dynamics, the data show complete spectral diffusion on the femtosecond-picosecond time scale with no static heterogeneity. This result indicates that this transition-state analogue complex completely samples the distribution of structu ...[more]

PMID: 18067303

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