Quantum chemical studies of methane monooxygenase: comparision with P450.
The catalytic pathways of soluble methane monooxygenase (sMMO) and cytochrome P450CAM, iron-containing enzymes, are described and compared. Recent extensive density functional ab initio electronic structure calculations have revealed many similarities in a number of the key catalytic steps, as well as some important differences. A particularly interesting and significant contrast is the role played by the protein in each system. For sMMO, the protein stabilizes various species in the catalytic cycle through a series of carboxylate shifts. This process is adequately described by a relatively compact model of the active site ( approximately 100 atoms), providing a reasonable description of the energetics of hydrogen atom abstraction. For P450CAM, in contrast, the inclusion of the full protein is necessary for an accurate description of the hydrogen atom abstraction.
Guallar
Victor
V
Department of Chemistry, Columbia University, New York, NY 10027, USA.
Gherman
Benjamin F
BF
Lippard
Stephen J
SJ
Friesner
Richard A
RA
D001665:Binding Sites; D002384:Catalysis; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D010105:Oxygenases / Q000737:chemistry* / Q000378:metabolism; D011789:Quantum Theory
D003577:Cytochrome P-450 Enzyme System; D010105:Oxygenases; C021555:methane monooxygenase