Chemoselective Installation of Amine Bonds on Proteins through Aza-Michael Ligation

• DOI: 10.1021/jacs.7b10702
• Publication Date: 2017-12-05T16:22:36Z
• Authors: Allyson M. Freedy; Maria J. Matos; Omar Boutureira; Francisco Corzana; Ana Guerreiro; Padma Akkapeddi; Víctor J. Somovilla; Tiago Rodrigues; Karl Nicholls; Bangwen Xie; Gonzalo Jiménez-Osés; Kevin M. Brindle; André A. Neves; Gonçalo J. L. Ber...
• Keywords: Bioorthogonal Chemistry; Native chemical ligation; Conjugate

Chemical modification of proteins is essential for a variety important diagnostic and therapeutic applications. Many strategies developed to date lack chemo- regioselectivity as well result in non-native linkages that may suffer from instability vivo adversely affect the protein's structure function. We describe here reaction N-nucleophiles with amino acid dehydroalanine (Dha) protein context. When Dha chemically installed proteins, addition wide-range enables rapid formation amine (secondary tertiary) chemoselective manner under mild, biocompatible conditions. These new are stable at wide range pH values (pH 2.8 12.8), reducing conditions (biological thiols such glutathione) human plasma. This method demonstrated three shown be fully compatible disulfide bridges, evidenced by selective recombinant albumin displays 17 structurally relevant disulfides. The practicability utility our approach further construction modified C2A domain Synaptotagmin-I retains its ability preferentially bind apoptotic cells level comparable native protein. Importantly, was useful building homogeneous antibody-drug conjugate precise drug-to-antibody ratio 2. kinase inhibitor crizotinib directly conjugated through piperidine motif, antibody-mediated intracellular delivery results 10-fold improvement cancer cell-killing efficacy. simplicity exquisite site-selectivity aza-Michael ligation described herein allows secondary tertiary amine-linked conjugates without affecting function biologically proteins.