The effect of heme environment on the hydrogen abstraction reaction of camphor in P450cam catalysis: a QM/MM study.
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.
Altun
Ahmet
A
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany.
Guallar
Victor
V
Friesner
Richard A
RA
Shaik
Sason
S
Thiel
Walter
W
D002164:Camphor / Q000737:chemistry* / Q000378:metabolism; D019475:Camphor 5-Monooxygenase / Q000737:chemistry* / Q000378:metabolism; D002384:Catalysis; D006418:Heme / Q000737:chemistry* / Q000378:metabolism; D006859:Hydrogen / Q000737:chemistry / Q000378:metabolism; D006900:Hydroxylation; D011789:Quantum Theory
D006418:Heme; D002164:Camphor; D006859:Hydrogen; D019475:Camphor 5-Monooxygenase