Bowman–Birk Inhibitors 

 Bowman–Birk proteinase inhibitor is a member of a widely studied family of serine proteinase inhibitors, protein. Most such inhibitors consists of a single polypeptide chain of 65–80 amino acid residues containing two homologous regions, each with a reactive site. In some Bowman–Birk inhibitors, both sites are specific for trypsin; in others, one is specific for trypsin and one for chymotrypsin; and, in still others, one is for trypsin and one for elastase. Ternary complexes of one inhibitor and two enzyme molecules are commonly found. The polypeptide chain is crosslinked by seven disulfide bridges, some within the homology regions, others between them, endowing the inhibitor with great stability.

References

T. Ikenaka and S. Norioka (1986) "Bowman–Birk family serine proteinase inhibitors". In Proteinase Inhibitors (A. Barrett and G. Salveson, eds.), Elsevier New York, 361–374.