The ONIOM Method and its Applications to Enzymatic Reactions

Fukui Institute for Fundamental Chemistry, Kyoto University, Takano Nishihiraki-cho 34-4, Kyoto 606-8103, Japan, email morokuma euch4e.chem.emory.edu 

Abstract ONIOM is a flexible hybrid scheme that can combine the most suitable computational 

Keywords ONIOM, QM/MM protein environmental effects, Bacteriorhodopsin, Methane, 

Monooxygenase, Isopenicillin N synthase, Glutathione peroxidase, Methylmalonyl-CoA mutase, PLP-dependent b-lyase 

Despite advent of theoretical methods and techniques and faster computers, no single theoretical method seems to be capable of reliable computational studies of reactivities of biocatalysts. Ab initio quantum mechanical (QM) methods may be accurate but are still too expensive to apply to large systems like biocatalysts. Semi-empirical quantum methods are not as accurate but are faster, but may not be fast enough for long time simulation of large molecular systems. Molecular mechanics (MM) force field methods are not usually capable of dealing with bond-breaking and formation 

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