Analysis of the Optical Rotatory Dispersion of Polypeptides and Proteins. IV. A Digital Computer Analysis for the Region 190-600 mμ1,2
Analysis of the Optical Rotatory Dispersion of Polypeptides and Proteins. IV. A Digital Computer Analysis for the Region 190-600 mμ1,2
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多肽和蛋白质的旋光色散分析 IV. 190-600 mμ1,2 区域的数字计算机分析。
DOI：
10.1021/ja00963a034
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发表时间：
1966
影响因子：
15
通讯作者：
E. Blout
中科院分区：
文献类型：
--
作者：
J. Carver;E. Shechter;E. Blout
由于缺乏将复杂的旋光色散曲线分解成其分量Cotton效应的方法，因此无法对实验和理论进行充分的比较。一个非线性的，最小二乘曲线拟合的方法来解释旋光色散数据被证明是有效的解决重叠的棉花效应，并揭示小棉花效应掩盖较大的相邻。将此方法应用于溶液中各种n-螺旋多肽的旋光色散数据（600 - 190 μ），所得结果与圆二色性和偏振紫外吸收光谱的结合所得出的结论一致，支持激子（对-*·*）和单电子（对n-**）模型。该方法也适用于旋光色散的随机形式的聚-α L-谷氨酸和聚-L-脯氨酸II螺旋。对于前者，发现三种柯顿效应，其中心分别为197.6、216.6和235 μ，旋转强度分别为-14.2 X 10-40、1.9 X 10 - 4和-0.13 X 10-40 erg cm 3。对于聚-L-脯氨酸II螺旋，发现了两个以206.9和221.0 μ为中心的Cotton效应，旋转强度分别为-33 X 10~ 40和5 X 10~ 40 erg cm ~ 3。它的结论是，需要进一步的理论工作之前，可以作出分配的“随机”多肽构象和聚-L-脯氨酸II螺旋的光学活性转换。
The lack of methods for resolving complex optical rotatory dispersion curves into their component Cotton effects has prevented an adequate comparison of experiment and theory. A nonlinear, least-squares curve fitting approach to the interpretation of optical rotatory dispersion data is shown to be effective in both resolving overlapping Cotton effects and revealing small Cotton effects obscured by larger ones adjacent to them. The appli-cation of this method to the optical rotatory dispersion data (from 600 to 190 µ) of various «-helical polypeptides in solution yields results agreeing with the conclusions from the combination of circular dichroism and polarized ultraviolet absorption spectra which support the exciton (for-*·*) and one-electron (for n-**) models. The method is also applied to the optical rotatory dispersion of the random form of poly-aL-glutamic acid and the poly-L-proline II helix. For the former, three Cotton effects are found centered at 197.6, 216.6, and 235 µ with rota-tional strengths—14.2 X 10-40, 1.9 X 10_4, and—0.13 X 10-40 erg cm3, respectively. For the poly-L-proline II helix, two Cotton effects are found centeredat 206.9 and 221.0 µ with rotational strengths—33 X 10~ 40 and 5 X 10~ 40 erg cm3, respectively. It is concluded thatfurther theoretical work is needed before assignments can be made for the optically active transitions of the “random" polypeptide conformation and the poly-L-proline II helix.