title: Effects of the protein environment on the structure and energetics of active sites of metalloenzymes. ONIOM study of methane monooxygenase and ribonucleotide reductase.
abstract: As the first application of our recently developed ONIOM2(QM:MM) and ONIOM3(QM:QM:MM) codes to the metalloenzymes with a large number of protein residues, two members of the non-heme protein family, methane monooxygenause and ribonucleotide reductase, have been chosen. The "active-site + four alpha-helical fragments" model was adopted which includes about 1000 atoms from 62 residues around the Fe-centered spheres. Comparison of the active-site geometries of MMOH and R2 units optimized with this model with those obtained with the "active site only" (with only 39-46 atoms) model and the X-ray results clearly demonstrates the crucial role of the active site-protein interaction in the enzymatic activities.
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, Michigan 48202, USA.
authors.forename: Maricel
authors.initials: M
authors.lastname: Torrent
authors.forename: Thom
authors.initials: T
authors.lastname: Vreven
authors.forename: Djamaladdin G
authors.initials: DG
authors.lastname: Musaev
authors.forename: Keiji
authors.initials: K
authors.lastname: Morokuma
authors.forename: Odön
authors.initials: O
authors.lastname: Farkas
authors.forename: H Bernhard
authors.initials: HB
authors.lastname: Schlegel
mesh_terms: D001665:Binding Sites; D010105:Oxygenases / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation; D012264:Ribonucleotide Reductases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D010105:Oxygenases; C021555:methane monooxygenase; D012264:Ribonucleotide Reductases