Target-Activated Coumarin Phototriggers Specifically Switch on Fluorescence and Photocleavage upon Bonding to Thiol-Bearing Protein
作者:Qiuning Lin、Chunyan Bao、Shuiyu Cheng、Yunlong Yang、Wei Ji、Linyong Zhu
DOI:10.1021/ja300475k
日期:2012.3.21
A new concept in which only the molecular target, such as a thiol-bearing protein, can activate the phototrigger has been demonstrated. Such target-activatable phototriggers comprise three parts: a 7-aminocoumarin phototrigger, an electron acceptor (maleimide) that efficiently quenches the coumarin excited state, and a caged leaving group attached to the coumarin. In the absence of mercaptans, photoinduced
已经证明了一种新概念,其中只有分子目标,如含硫醇的蛋白质,才能激活光触发。这种目标可激活的光触发器包括三部分:7-氨基香豆素光触发器、有效淬灭香豆素激发态的电子受体(马来酰亚胺)和连接到香豆素的笼状离去基团。在没有硫醇的情况下,香豆素和马来酰亚胺之间的光诱导电子转移有效地阻断了荧光和光裂解途径。然而,含硫醇的分子很容易消灭电子受体,从而恢复用于光释放笼中货物(例如生物素)的光触发。与传统的光触发器不同,官能团激活的光触发器允许在环境光下轻松处理,报告与目标的特定结合,并在原位选择性地在结合位点启用光裂解能力,从而有效地将光释放的货物定位在目标处。同时,硫醇特异性激活荧光和光裂解的独特特征使我们的新光触发器成为一种通用工具,可用于准确识别蛋白质半胱氨酸 S-亚硝基化,这是一种生理学上重要的翻译后修饰。