Abstract: Lis-Pro modified proinsulin sequences that have a modified C-peptide amino acid and/or nucleic acid modification are presented. Methods for producing Lis-Pro insulin analogs are also disclosed. Highly efficient processes for preparing the Lis-Pro insulin analogs and improved preparations containing the Lis-Pro insulin analogs prepared according to the methods described herein are also provided.

Abstract: Disclosed herein are novel and improved preparations and methods for manufacturing substantially liquid preparations of recombinant human insulin API. The purified recombinant human insulin Active Pharamaceutical Ingredient (API) preparations are substantially free of by-products associated with the lyophilization and/or crystallization. The methods for manufacturing the substantially liquid recombinant human insulin API preparations are provided with optional steps for subjecting the recombinant insulin preparation to lyophilization and/or crystallization. Enhanced yield of recombinant insulin of greater purity are thereby provided according to the present invention. Highly purified formulations of recombinant human insulin of the API insulin preparations disclosed herein are also provided. Stably transformed E.