Secondary amine selective Petasis (SASP) bioconjugation
Secondary amine selective Petasis (SASP) bioconjugation
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DOI：
10.1039/c9sc04697f
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发表时间：
2020-01-07
期刊：
影响因子：
8.4
通讯作者：
Raj, Monika
中科院分区：
文献类型：
--
作者：
Sim, Yonnette E.;Nwajiobi, Ogonna;Raj, Monika
蛋白质的选择性修饰使抗体-药物结合物的合成、细胞药物输送和新材料的构建成为可能。许多基团已经开发出通过适当的pH控制在不影响赖氨酸侧链的情况下选择性地对N-末端进行修饰的方法。这是因为相对于赖氨酸侧链，N-末端的碱性较低。但这些方法都不能选择性地修饰与赖氨酸具有相似碱性的仲胺或N-末端的脯氨酸。在这里，我们报告了一个次胺选择性配基(SASP)反应，用于N-末端的选择生物连接。我们利用仲胺与醛形成高度亲电的金属离子的能力，使其与亲核的有机硼化合物快速反应，从而在生物相容的条件下对N-末端的脯氨酸进行了强有力的标记。这是第一次利用Petsis反应在生理条件下对完全不受保护的多肽和蛋白质进行仲胺的选择性修饰。多肽筛选结果表明，该反应对N-末端的脯氨酸具有很高的选择性。在文献中还没有报道的其他化学方法对多肽和蛋白质中的N-末端脯氨酸具有选择性。这是一个多组分的反应，导致在一步内合成双官能化生物结合物，这是使用其他方法难以实现的。SASP反应的主要优点包括其高度的化学选择性和立体选择性(>；99%de)，并且它在一个锅中提供双重标记的蛋白质。这种生物偶联的广泛用途被强调用于各种多肽和蛋白质，包括醛缩酶和肌酸激酶。
Selective modification of proteins enables synthesis of antibody-drug conjugates, cellular drug delivery and construction of new materials. Many groups have developed methods for selective N-terminal modification without affecting the side chain of lysine by judicious pH control. This is due to lower basicity of the N-terminus relative to lysine side chains. But none of the methods are capable of selective modification of secondary amines or N-terminal proline, which has similar basicity as lysine. Here, we report a secondary amine selective Petasis (SASP) reaction for selective bioconjugation at N-terminal proline. We exploited the ability of secondary amines to form highly electrophilic iminium ions with aldehydes, which rapidly reacted with nucleophilic organoboronates, resulting in robust labeling of N-terminal proline under biocompatible conditions. This is the first time the Petasis reaction has been utilized for selective modification of secondary amines on completely unprotected peptides and proteins under physiological conditions. Peptide screening results showed that the reaction is highly selective for N-terminal proline. There are no other chemical methods reported in literature that are selective for N-terminal proline in both peptides and proteins. This is a multicomponent reaction leading to the synthesis of doubly functionalized bioconjugates in one step that can be difficult to achieve using other methods. The key advantage of the SASP reaction includes its high chemoselective and stereoselective (>99% de) nature, and it affords dual labeled proteins in one pot. The broad utility of this bioconjugation is highlighted for a variety of peptides and proteins, including aldolase and creatine kinase.