Recombinant human proinsulin: oxidative refolding and biophysical characterization

ALEJO R. GIANOTTI; DIEGO S. VAZQUEZ; PAMELA TOLEDO; JUHA TORKKO; MICHELE SOLIMENA; MARIO R. ERMÁCORA

CABA

Congreso; XLIX Reunión Anual de la Sociedad Argentina de Biofísica; 2021

SAB

According to the World Health Organization, diabetes is a global health priority. Growing prevalence of diabetes worldwide will increase the demand for insulin in the near future, which is especially challenging in developing countries. For this reason, it is pertinent to reexamine the in vitro production of insulin. Moreover, our knowledge of insulin folding in vivo is insufficient and needs to be advanced.Human insulin is synthesized in vivo as a single-chain precursor, proinsulin, from which a middle peptide, C-peptide, is post-translationally removed generating the biologically active insulin. To fold correctly, proinsulin must first form three disulphide bonds linking chains A and B of mature insulin. This critical step, both in vivo and in vitro, is incompletely understood. In this work we describe the optimization of the downstream processing of oxidative refolding of the recombinant human proinsulin expressed in E. coli. We successfully obtained native human proinsulin in large amounts, highly pure and properly folded. Furthermore, we report a preliminary biophysical characterization of human proinsulin.