H-Ala-Leu-Cys-Asn-Cys-Asn-Arg-Ile-Ile-Ile-Pro-His-Met-Cys-Trp-Lys-Lys-Cys-Gly-Lys-Lys-NH2 (Disulfide bonds between Cys³ and Cys¹⁴/Cys⁵ and Cys¹⁸)