Ligand-induced differences in secondary structure of the Vibrio parahaemolyticus Na+/galactose cotransporter.
Ligand-induced differences in secondary structure of the Vibrio parahaemolyticus Na+/galactose cotransporter.
复制标题
配体诱导的副溶血性弧菌 Na /半乳糖协同转运蛋白二级结构的差异。
DOI：
10.1021/bi025692d
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发表时间：
2002
期刊：
影响因子：
2.9
通讯作者：
Wright,ErnestM
中科院分区：
文献类型：
--
作者：
leCoutre,Johannes;Turk,Eric;Kaback,HRonald;Wright,ErnestM
利用衰减全反射傅里叶变换红外光谱对副溶血性弧菌原核生物钠/半乳糖转运体(VSGLT)的结构进行了详细的研究，发现钠和d-半乳糖结合后，α螺旋度逐渐增加。这些螺旋度的增加与β结构元件的减少相关。伴随着这些变化的是H/D交换度(HDX)的逐步降低，这表明蛋白质骨架对水的可及性降低。这些数据显示了在蛋白质的催化循环中，从一个中间体到下一个中间体的离散构象变化，并用符号反应机制的模型进行了解释。
A detailed structural study of the prokaryotic sodium/galactose transporter (vSGLT) fromVibrio parahaemolyticususing attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy reveals stepwise increases in α-helicity upon binding of sodium andd-galactose. These increases in helicity correlate with decreases in β-structural elements. The changes are accompanied by stepwise reductions in the degree of H/D exchange (HDX), suggesting reduced accessibility of water to the protein backbone. The data demonstrate discrete conformational changes from one intermediate to the next during the catalytic cycle of the protein and are interpreted in a model of the symport reaction mechanism.