A protecting group for carboxylic acids that can be photolyzed by visible light
A protecting group for carboxylic acids that can be photolyzed by visible light
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DOI：
10.1021/bi047665o
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发表时间：
2005-05-17
期刊：
影响因子：
2.9
通讯作者：
Hess, GP
中科院分区：
文献类型：
--
作者：
Shembekar, VR;Chen, YL;Hess, GP
我们报告的光不稳定的保护（笼）组，这是新的羧酸。与以前用于羧酸的笼状基团不同，它可以在可见光波长范围内快速有效地光解。笼化基团7-N，N-二乙基氨基香豆素（DECM）用于笼化谷氨酸的γ-羧基，谷氨酸也是一种神经递质。笼状化合物的主要吸收带最大值位于390 nm（λ（390）= 13651 M-1 cm（-1））。实验在400 nm（λ（400）= 12232 M-1 cm（-1））和更长的波长下进行。DECM笼状谷氨酸盐是水溶性的，在pH 7.4和22 ℃下稳定。它在水溶液中迅速光解，在3 μ s内释放谷氨酸，在可见光区的量子产率为0.11 +/- 0.008。在全细胞电流记录实验中，使用表达谷氨酸受体的HEK-293细胞和可见光进行光解，发现DECM笼状谷氨酸及其光解副产物是生物惰性的。由各种含羧基化合物激活的神经递质受体在神经系统的类似于10（12）个神经元之间的信号传递中起核心作用。笼状神经递质已成为一个重要的工具，在瞬态动力学研究的神经递质受体的作用机制。在此之前，将适合于瞬态动力学研究的化合物打开需要紫外光和昂贵的激光，因此需要特别的预防措施。适用于瞬态动力学研究的笼状神经递质的可用性，可以通过可见光光解允许使用简单易用，容易获得的廉价光源，从而打开了这个重要的领域，越来越多的调查。
We report on a photolabile protecting (caging) group that is new for carboxylic acids. Unlike previously used caging groups for carboxylic acids, it can be photolyzed rapidly and efficiently in the visible wavelength region. The caging group 7-N,N-diethyl aminocoumarin (DECM) was used to cage the gamma-carboxyl group of glutamic acid, which is also a neurotransmitter. The caged compound has a major absorption band with a maximum at 390 nm (epsilon(390) = 13651 M-1 cm(-1)). Experiments are performed at 400 nm (epsilon(400) = 12232 M-1 cm(-1)) and longer wavelengths. DECM-caged glutamate is water soluble and stable at pH 7.4 and 22 degrees C. It photolyzes rapidly in aqueous solution to release glutamic acid within 3,us with a quantum yield of 0.11 +/- 0.008 in the visible region. In whole-cell current-recording experiments, using HEK-293 cells expressing glutamate receptors and visible light for photolysis, DECM-caged glutamate and its photolytic byproducts were found to be biologically inert. Neurotransmitter receptors that are activated by various carboxyl-group-containing compounds play a central role in signal transmission between similar to 10(12) neurons of the nervous system. Caged neurotransmitters have become an essential tool in transient kinetic investigations of the mechanism of action of neurotransmitter receptors. Previously uncaging the compounds suitable for transient kinetic investigations required ultraviolet light and expensive lasers, and, therefore, special precautions. The availability of caged neurotransmitters suitable for transient kinetic investigations that can be photolyzed by visible light allows the use of simple-to-use, readily available inexpensive light sources, thereby opening up this important field to an increasing number of investigators.