Najbar L V, Craik D J, Wade J D, Salvatore D, McLeish M J
Victorian College of Pharmacy, Monash University, 381 Royal Pde, Parkville 3052, Australia.
Biochemistry. 1997 Sep 23;36(38):11525-33. doi: 10.1021/bi970730s.
The solution conformation of a peptide LYS(11-36), which corresponds to the beta-sheet region in T4 lysozyme, has been examined in aqueous solution, TFE, and SDS micelles by CD and 1H NMR spectroscopy. Secondary structure predictions suggest some beta-sheet and turn character in aqueous solution but predict a helical conformation in a more hydrophobic environment. The predictions were supported by the CD and NMR studies which showed the peptide to be relatively unstructured in aqueous solution, although there was some evidence of a beta-turn conformer which was maintained in 200 mM SDS and, to a lesser extent, in 50% TFE. The peptide was significantly helical in the presence of either 50% TFE or 200 mM SDS. TFE and SDS titrations showed that the peptide could form helical, sheet, or extended structure depending on the TFE or SDS concentration. The studies indicate that peptide environment is the determining factor in secondary structure adopted by LYS(11-36).
通过圆二色光谱（CD）和核磁共振氢谱（1H NMR）对一种对应于T4溶菌酶β折叠区域的肽LYS(11 - 36)在水溶液、三氟乙醇（TFE）和十二烷基硫酸钠（SDS）胶束中的溶液构象进行了研究。二级结构预测表明该肽在水溶液中具有一些β折叠和转角特征，但预测在更疏水的环境中会形成螺旋构象。圆二色光谱和核磁共振研究支持了这些预测，研究表明该肽在水溶液中相对无结构，尽管有一些证据表明存在一种β转角构象体，其在200 mM SDS中得以维持，在50% TFE中维持程度稍低。在50% TFE或200 mM SDS存在的情况下，该肽呈显著的螺旋结构。TFE和SDS滴定表明，该肽可根据TFE或SDS浓度形成螺旋、折叠或伸展结构。这些研究表明，肽的环境是LYS(11 - 36)所采用二级结构的决定因素。
