Study cases of enzymatic processes

Peptides are heteropolymers composed by amino acid residues linked by peptidic bonds between the carboxyl group of one amino acid residue and the α-amino group of the next one. The definition is rather vague in terms of chain length, peptides ranging from two residues to a few dozens residues. Its upper limit of molecular mass has been set rather arbitrarily in 6,000 Da. The size of the molecule determines the technology most suitable for its production. Recombinant DNA technology is particularly suitable for the synthesis of large peptides and proteins, as illustrated by the case of insulin and other hormones (Walsh 2005). Chemical synthesis is a viable technology for the production of small and medium size peptides ranging from about 5 to 80 residues (Kimmerlin and Seebach 2005). Enzymatic synthesis is more restricted and has been hardly applied for the synthesis of peptides exceeding 10 residues. Its potential relies on the synthesis of very small peptides and, in fact, most of the cases reported correspond to dipeptides and tripeptides (Kumar and Bhalla 2005). In this sense, the technologies for peptide production are not competitive with each other in most of the cases.