Except for some of the originally studied enzymes such as pepsin, rennin, and trypsin, most enzyme names end in "ase". The International Union of Biochemistry (I.U.B.) initiated standards of enzyme nomenclature which recommend that enzyme names indicate both the substrate acted upon and the type of reaction catalyzed. Under this system, the enzyme uricase is called urate: O2 oxidoreductase, while the enzyme glutamic oxaloacetic transaminase (GOT) is called L-aspartate: 2-oxoglutarate aminotransferase.
Enzymes can be classified by the kind of chemical reaction catalyzed.
Addition or removal of water
Hydrolases - these include esterases, carbohydrases, nucleases, deaminases, amidases, and proteases
Hydrases such as fumarase, enolase, aconitase and carbonic anhydrase
Transfer of electrons
Oxidases
Dehydrogenases
Transfer of a radical
Transglycosidases - of monosaccharides
Transphosphorylases and phosphomutases - of a phosphate group
Transaminases - of amino group
Transmethylases - of a methyl group
Transacetylases - of an acetyl group
Splitting or forming a C-C bond
Desmolases
Changing geometry or structure of a molecule
Isomerases
Joining two molecules through hydrolysis of pyrophosphate bond in ATP or other tri-phosphate