A Pictet-Spengler ligation for protein chemical modification
作者:Paresh Agarwal、Joep van der Weijden、Ellen M. Sletten、David Rabuka、Carolyn R. Bertozzi
DOI:10.1073/pnas.1213186110
日期:2013.1.2
Their reactive carbonyl groups are typically conjugated with alpha-effect nucleophiles, such as substituted hydrazines and alkoxyamines, to generate hydrazones and oximes, respectively. However, the resulting C=N linkages are susceptible to hydrolysis under physiologically relevant conditions, which limits the utility of such conjugates in biological systems. Here we introduce a Pictet-Spengler ligation
醛和酮功能化蛋白质是开发化学改性生物治疗剂和蛋白质材料的有吸引力的底物。它们的反应性羰基通常与α效应亲核试剂(例如取代的肼和烷氧基胺)共轭,分别生成腙和肟。然而,由此产生的 C=N 键在生理相关条件下易于水解,这限制了此类缀合物在生物系统中的应用。在这里,我们介绍了基于醛和色胺亲核试剂的经典 Pictet-Spengler 反应的 Pictet-Spengler 连接。连接利用醛和烷氧基胺的生物正交反应形成中间体氧亚胺离子;该中间体与吲哚亲核试剂形成分子内 CC 键,形成水解稳定的奥沙咔啉产物。我们使用该反应对乙醛酰和甲酰甘氨酸功能化蛋白质进行位点特异性化学修饰,包括治疗性单克隆抗体赫赛汀的醛标记变体。结合位点特异性将醛引入蛋白质的技术,Pictet-Spengler 连接提供了一种产生用于医疗和材料应用的稳定生物偶联物的方法。
PICTET-SPENGLER LIGATION FOR PROTEIN CHEMICAL MODIFICATION
申请人:THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
公开号:US20150291699A1
公开(公告)日:2015-10-15
Aldehyde- and ketone-functionalized proteins are promising new substrates for the development of chemically modified biotherapeutics and protein-based materials. Their reactive carbonyl groups are typically conjugated with a-effect nucleophiles, such as substituted hydrazines and alkoxyamines, to generate hydrazones and oximes, respectively. However, the resulting C═N linkages are susceptible to hydrolysis under physiologically relevant conditions, which limits their utility in biological systems. Here we introduce a Pictet-Spengler ligation that is based on the classic Pictet-Spengler reaction of aldehydes and tryptamine nucleophiles. The ligation exploits the bioorthogonal reaction of aldehydes and alkoxyamines to form an intermediate oxyiminium ion; this intermediate undergoes intramolecular C—C bond formation with an indole nucleophile to form an oxacarboline product that is hydrolytically stable. The reaction was utilized for site-specific chemical modification of glyoxal- and formylglycine-functionalized proteins, including an aldehyde-tagged variant of the therapeutic monoclonal antibody Herceptin. In conjunction with techniques for site-specific introduction of aldehydes into proteins, the Pictet-Spengler ligation offers a new means to generate stable bioconjugates for medical and materials applications.
KAHA Ligations That Form Aspartyl Aldehyde Residues as Synthetic Handles for Protein Modification and Purification
作者:Claudia E. Murar、Frédéric Thuaud、Jeffrey W. Bode
DOI:10.1021/ja511231f
日期:2014.12.31
semialdehyde (Asa) side chain can be easily prepared by a chemoselective amide-formingligation that results in the formation of the Asa residue at the ligation site. This strategy employs the α-ketoacid-hydroxylamine (KAHA) ligation in combination with a new isoxazolidine monomer that forms a side-chain aldehyde upon ligation. This monomer is easily prepared on a preparative scale by a catalytic, enantioselective