Well, we can do catalysis using transition metals. Can we do the same in biological systems? Moreover, can we do biochemical transformations? The answer is yes, we can and here are a few examples of these remarkable processes.
In this brief review, you can read several examples of metal catalyzed cross coupling reactions for fluorescent labelling, deprotection of azides/carbamates, activation of metallodrugs, cleavage of peptides, nucleic acid chains and proteins (HIV1, RNA etc.), using NADH for transfer hydrogenation and many more transformations that are done in biochemical environment. Some of them are their infancy, but there are some in Phase II/III stages and there is even one approved in Russia.