Preparations and properties of crystalline porcine and bovine [Trp]B1 insulins.

[Trp]B1 analogs to porcine and bovine insulins have been obtained through selective reaction with Msc-ONSu, and followed by Edman degradation, condensation with Msc-Trp-ONp and deprotection. Through cellulose acetate electrophoresis, amino acid composition analysis, UV absorption spectrum and N-terminal analysis, it has been proved that the products are of purified [Trp]B1 insulin. Mouse convulsion assay shows that the biological activities of porcine and bovine [Trp]B1 insulins are 18 i.u./mg and 17 i.u./mg respectively, corresponding to about 70% of the original activity of native porcine insulin. Their structural details are under investigation in our laboratory.