Trans/cis (Z/E) photoisomerization of the chromophore of photoactive yellow protein is not a prerequisite for the initiation of the photocycle of this photoreceptor protein.
Trans/cis (Z/E) photoisomerization of the chromophore of photoactive yellow protein is not a prerequisite for the initiation of the photocycle of this photoreceptor protein.
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光敏黄色蛋白发色团的反式/顺式 (Z/E) 光异构化并不是该光感受器蛋白光循环启动的先决条件。
DOI：
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发表时间：
1998
影响因子：
11.1
通讯作者：
K. Hellingwerf
中科院分区：
文献类型：
--
作者：
Robert Cordfunke;R. Kort;A. J. Pierik;B. Gobets;Gert;Jan W. Verhoeven;K. Hellingwerf
光敏黄蛋白（PYP）的发色团（即，4-羟基肉桂酸）已被具有三键而不是双键的类似物（通过在重构中使用4-羟基苯基丙炔酸，产生杂合物I）和“锁定”发色团（通过与7-羟基香豆素-3-羧酸重构，其中存在跨越乙烯基键的共价桥，产生杂合物II）取代。这些杂化物分别在464和443 nm处吸收最大，这表明在这两种杂化物中，去质子化的发色团确实适合发色团结合口袋。由于三键不能经历顺式/反式（或E/Z）光异构化，并且由于杂合物II中乙烯基双键上的锁的存在，预测这两种杂合物将不能光循环。令人惊讶的是，两者都能。我们已经证明了这种能力，利用瞬态吸收，低温吸收，傅里叶变换红外光谱（FTIR）。这两种混合物，在光激发，显示真实的光循环信号的红移中间体;混合物I，此外，通过一个蓝移样的中间状态，具有非常缓慢的动力学。我们解释这些结果作为进一步的证据，旋转的硫酯连接的发色团的PYP，提出在以前的FTIR研究和可视化在最近的时间分辨的X-射线衍射实验，是至关重要的PYP的光活化。
The chromophore of photoactive yellow protein (PYP) (i.e., 4-hydroxycinnamic acid) has been replaced by an analogue with a triple bond, rather than a double bond (by using 4-hydroxyphenylpropiolic acid in the reconstitution, yielding hybrid I) and by a "locked" chromophore (through reconstitution with 7-hydroxycoumarin-3-carboxylic acid, in which a covalent bridge is present across the vinyl bond, resulting in hybrid II). These hybrids absorb maximally at 464 and 443 nm, respectively, which indicates that in both hybrids the deprotonated chromophore does fit into the chromophore-binding pocket. Because the triple bond cannot undergo cis/trans (or E/Z) photoisomerization and because of the presence of the lock across the vinyl double bond in hybrid II, it was predicted that these two hybrids would not be able to photocycle. Surprisingly, both are able. We have demonstrated this ability by making use of transient absorption, low-temperature absorption, and Fourier-transform infrared (FTIR) spectroscopy. Both hybrids, upon photoexcitation, display authentic photocycle signals in terms of a red-shifted intermediate; hybrid I, in addition, goes through a blue-shifted-like intermediate state, with very slow kinetics. We interpret these results as further evidence that rotation of the carbonyl group of the thioester-linked chromophore of PYP, proposed in a previous FTIR study and visualized in recent time-resolved x-ray diffraction experiments, is of critical importance for photoactivation of PYP.
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影响因子：
2.9
作者：
Munsok Kim;R. Mathies;W. Hoff;K. Hellingwerf
通讯作者：
Munsok Kim;R. Mathies;W. Hoff;K. Hellingwerf
细菌视紫红质及其用氘代酪氨酸再生的光产物的傅里叶变换红外差异光谱。
影响因子：
2.9
作者：
Dollinger,G;Eisenstein,L;Lin,SL;Nakanishi,K;Termini,J
通讯作者：
Termini,J
具有 11-顺式锁八元环视网膜的不可漂白视紫红质：视觉转导过程。
影响因子：
2.9
作者：
Hu,S;Franklin,PJ;Wang,J;RuizSilva,BE;Derguini,F;Nakanishi,K;Chen,AH
通讯作者：
Chen,AH
DOI：
10.1016/0005-2728(85)90094-5
发表时间：
1985-01-01
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA
影响因子：
--
作者：
MEYER, TE
通讯作者：
MEYER, TE
影响因子：
2.9
作者：
BORGSTAHL, GEO;WILLIAMS, DR;GETZOFF, ED
通讯作者：
GETZOFF, ED