Typical degradation reactions are:
- Oxidation of Met yielding the sulfoxide
- Oxidation of Trp and Tyr
- Oxidation of Cys to cysteic acid
- Deamidation of Asn, Gln, and the C-terminal amide
- Aspartimide formation
- Cleavage of Asn-Pro
- Pyroglutamine formation of N-terminal Gln
- (Cyclization of N-terminal Glu has only rarely been observed)
- Dimerization of Trp and Tyr
- Racemization