Transferases catalyze the transfer of functional groups such as alkyl, methyl, acyl, carbonyl, hydroxymethyl, phosphoryl, glycosyl, carboxyl, and sulfate, from a donor molecule to an acceptor molecule. Transferases are involved in numerous biochemical reactions in the cell.

For example, during translation, the peptidyl transferase catalyzes the transfer of an amino acid chain, which is a functional group, from the tRNA molecule in the A-site of the ribosome to the tRNA in the P-site