(A chain) Glp Asp Leu Gln Thr Leu Cys Cys Thr Asp Gly Cys Ser Met
Thr Asp Leu Ser Ala Leu Cys (Disulfide bridge: 7-12)
(B chain) Lys Glu Ser Val Arg Leu Cys Gly Leu Glu Tyr Ile Arg Thr
Val Ile Tyr Ile Cys Ala Ser Ser Arg Trp
(Disulfide bridge: A8-B7; A21-B19)