Metal Ions Present in Biomacromolecules

In many cases the metal ion and the binding of the ligands play an important catalytic role, and the study of this role is the main theme of the present monograph. This catalysis role can be in electron transfer only it can also be a complicated redox reaction, or a relatively simple acid-base reaction. The presence of the metal at the particular site usually results in activation reactions of substrates by the metal and the surrounding ligands. 

All enzymes were classified many years ago into six major groups,an important classification which also holds for the many metal-containing enzymes and which is used worldwide. 

Transferases (transferring an organic group from a donor molecule to an acceptor molecule)  

Isomerases (geometric or structural change within a molecule)  

Ligases (these join together two molecules or fragments often coupled with pyrophosphate hydrolysis). 

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