Facile synthesis of insulin fusion derivatives through sortase A ligation

摘要

Insulin derivatives such as insulin detemir and insulin degludec are U.S.Food and Drug Administration(FDA)-approved long-acting insulin currently used by millions of people with diabetes.These derivatives are modified in C-terminal B29 lysine to retain insulin bioactivity.New and efficient methods for facile synthesis of insulin derivatives may lead to new discovery of therapeutic insulin.Herein,we report a new method using sortase A(SrtA)-mediated ligation for the synthesis of insulin derivatives with high efficiency and functional group tolerance in the C-terminal B chain.This new insulin molecule(Ins-SA) with an SrtA-recognizing motif can be conjugated to diverse groups with N-terminal oligoglycines to generate new insulin derivatives.We further demonstrated that a new insulin derivative synthesized by this SrtA-mediated ligation shows strong cellular and in vivo bioactivity.This enzymatic method can therefore be used for future insulin design and development.