Vibrational circular dichroism spectra of proteins in the amide III region: measurement and correlation of bandshape to secondary structure.
Vibrational circular dichroism spectra of proteins in the amide III region: measurement and correlation of bandshape to secondary structure.
复制标题
酰胺 III 区蛋白质的振动圆二色光谱：带形与二级结构的测量和相关性。
DOI：
10.1006/abio.1997.2221
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Keiderling,TA
中科院分区：
文献类型：
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作者：
Baello,BI;Pancoska,P;Keiderling,TA
振动圆二色性（VCD）光谱已经测量了23个溶解在H2O/磷酸盐缓冲液中的球状蛋白质在1400至1100 cm− 1区域内的振动圆二色性（VCD）光谱，该区域包括酰胺III模式。光谱响应特征的主要二级结构类型被发现作为广泛的功能在1300 cm−1，与极端形式具有积极的VCD高度螺旋蛋白质和负VCD高度含片蛋白质。使用先前开发的因子分析和限制性多元回归（FA/RMR）技术与二级结构进行定量相关。由于酰胺III模式的吸光度强度由于与其他跃迁重叠而难以确定，因此使用了另一种绝对强度独立的简单结构分析方法。一个线性回归之间的二级结构的蛋白质集和重叠积分的归一化光谱的分数组件与选定的蛋白质。这种简单的方法的结果是相当的FA/RMR方法与酰胺III VCD分析。另一方面，当与电子CD光谱一起使用时，新方法的测试计算不如FA/RMR，因为它与二级结构的关系更依赖于强度。
Vibrational circular dichroism (VCD) spectra have been measured for 23 globular proteins dissolved in H2O/phosphate buffer over the 1400 to 1100 cm−1region which encompasses the amide III mode. Spectral responses characteristic of the dominant secondary structure type were found as broad features at ∼1300 cm−1, with the extreme forms having positive VCD for highly helical proteins and negative VCD for highly sheet-containing proteins. Quantitative correlation with secondary structure was carried out using previously developed factor analysis and restricted multiple regression (FA/RMR) techniques. Since the absorbance intensity of the amide III mode is difficult to determine due to overlap with other transitions, an alternative, absolute intensity-independent, simple structural analysis method was used. A linear regression was developed between the fractional components of secondary structure for the protein set and the overlap integrals of the normalized spectra from the set with that of a selected protein. The results of this simple method are quite comparable to those of the FA/RMR approach for analysis with amide III VCD. On the other hand, test calculations with the new method when used with electronic CD spectra are not as good as FA/RMR due to its more intensity-dependent relationship with secondary structure.