Bolotina I A, Chekhov V O, Lugauskas V Iu, Finkel'shteĭn A V, Ptitsyn O B
Mol Biol (Mosk). 1980 Jul-Aug;14(4):891-902.
It is shown that to obtain the protein-derived basic CD spectra for alpha-helical, beta-structural and irregular regions it is necessary to use a common criterion for isolation of secondary structures for all the reference proteins. Using the "rigid" criterion proposed by Finkelstein, Ptitsyn, Kozytsyn and the "mild" one (as proposed by Levitt and Greer) isolation of the alpha- and beta-structural regions for 5 reference proteins (myoglobin, lysozyme, ribonuclease A, papain, lactate dehydrogenase) has been carried out. Using the f alpha, f beta and f irregular thus obtained and the experimental CD spectra of these proteins, the basic CD spectra for alpha-helical, beta-structural and irregular regions in the proteins have been calculated. It is shown that the use of criterions common for all the proteins leads to good agreement between the calculated basic CD spectra for alpha-helical, beta-structural and irregular forms and the CD spectra of polylysine in the corresponding conformations. The secondary structure of the proteins studied has been analysed using the new protein-derived basic spectra and fairly good quantitative agreement with the X-ray data was achieved.
结果表明，要获得α螺旋、β结构和不规则区域的蛋白质衍生基本圆二色光谱，必须对所有参考蛋白质使用一个共同的二级结构分离标准。使用芬克尔斯坦、普季茨yn、科齐茨yn提出的“严格”标准和莱维特与格里尔提出的“温和”标准，对5种参考蛋白质（肌红蛋白、溶菌酶、核糖核酸酶A、木瓜蛋白酶、乳酸脱氢酶）的α和β结构区域进行了分离。利用由此获得的fα、fβ和f不规则值以及这些蛋白质的实验圆二色光谱，计算了蛋白质中α螺旋、β结构和不规则区域的基本圆二色光谱。结果表明，对所有蛋白质使用共同的标准会使计算得到的α螺旋、β结构和不规则形式的基本圆二色光谱与相应构象的聚赖氨酸圆二色光谱之间有很好的一致性。利用新的蛋白质衍生基本光谱对所研究蛋白质的二级结构进行了分析，并与X射线数据取得了相当好的定量一致性。
