[Semisynthetic sheep des-A1-glycine insulin (author's transl)]

The synthetic Des-1-glycine-A-chain of sheep insulin as the monomeric cyclic bisdisulfide and native bovine B-chain bissulfonate were reduced together with mercaptoethanol. They combined at pH 10.6 to yield Des-A1-glycine-insulin. This was purified by gel and ion exchange chromatography. The low insulin activity (0.4 - 0.6%) as measured by the fat cell test as well as the change in the CD spectrum indicated that the loss of the N-terminal glycine of the A-chain results in fully inactive insulin. This confirms the results obtained earlier by partial synthesis of Des-A1-glycine-insulin.