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The effect of heme environment on the hydrogen abstraction reaction of camphor in P450cam catalysis: a QM/MM study.

ABSTRACT: The discrepancies between the published QM/MM studies (Schöneboom, J. C.; Cohen, S.; Lin, H.; Shaik, S.; Thiel, W. J. Am. Chem. Soc. 2004, 126, 4017; Guallar, V.; Friesner, R. A. J. Am. Chem. Soc. 2004, 126, 8501) on H-abstraction of camphor in P450cam have largely been resolved. The crystallographic water molecule 903 situated near the oxo atom of Compound I acts as a catalyst for H-abstraction, lowering the barrier by about 4 kcal/mol. Spin density at the A-propionate side chain of heme can occur in the case of incomplete screening but has no major effect on the computed barrier.

SUBMITTER: Altun A

PROVIDER: S-EPMC3025707 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature

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The effect of heme environment on the hydrogen abstraction reaction of camphor in P450cam catalysis: a QM/MM study.

Altun Ahmet A Guallar Victor V Friesner Richard A RA Shaik Sason S Thiel Walter W

Journal of the American Chemical Society 20060301 12

The discrepancies between the published QM/MM studies (Schöneboom, J. C.; Cohen, S.; Lin, H.; Shaik, S.; Thiel, W. J. Am. Chem. Soc. 2004, 126, 4017; Guallar, V.; Friesner, R. A. J. Am. Chem. Soc. 2004, 126, 8501) on H-abstraction of camphor in P450cam have largely been resolved. The crystallographic water molecule 903 situated near the oxo atom of Compound I acts as a catalyst for H-abstraction, lowering the barrier by about 4 kcal/mol. Spin density at the A-propionate side chain of heme can oc ...[more]

PMID: 16551096

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