Model studies of the structures, reactivities, and reaction mechanisms of metalloenzymes

Electronic structure theory, which in recent years has been actively and ef fectively applied to the modeling of chemical reactions involving transitio n-metal complexes, is now also being applied to the modeling of biological processes involving metalloenzymes. In the first part of this paper, we rev iew our recent electronic structure studies using relatively simple models of two metalloenzymes - methane monooxygenase and ribonucleotide reductase. In the second part of the paper, we review a new hybrid theoretical method we have developed for modeling the reactivities of large molecular systems . We describe the limitations of these models and indicate how they may be further improved to reliably model the reactivities of complicated metalloe nzymes.