Delving Deep into the Structural Aspects of the BPro28-BLys29 Exchange in Insulin Lispro: A Structural Biophysical Lesson

Insulin lispro was the first fast acting insulin analogue to obtain regulatory approval for therapeutic use. This article puts forward a novel biophysical mechanism where the net impact of the simple B28Pro-B29Lys exchange from regular insulin to insulin lispro is the establishment of a novel set of interfacial electrostatic interactions between Lys28 of insulin lispro and Asp12 of insulin receptor (IR). In addition, a set of structural analysis was presented in this article to further strengthen the binding of insulin lispro to IR, where two polar amino acid residues (Gln51 and Asn74 of insulin lispro) were put forward as two potential targets for site-directed mutagenesis of insulin lispro at its binding interface with IR.