Kokkinidis M, Banner D W, Tsernoglou D, Brückner H
Biochem Biophys Res Commun. 1986 Sep 14;139(2):590-5. doi: 10.1016/s0006-291x(86)80031-6.
The crystal structure of L-prolyl-L-leucyl-alpha-aminoisobutyryl-alpha- aminoiso-butyryl-alpha-L-glutamyl-L-valinol (L-Pro-L-Leu-Aib-Aib-L-Glu-L-Valol), the C-terminal hexapeptide fragment of trichotoxin, has been determined by X-ray crystallography. The hexapeptide forms a right-handed 3(10)-helix consisting of two 10-atom hydrogen-bonded beta-turns of type III and one beta-turn of type I. Two of the intramolecular hydrogen-bonds are particularly weak, thus suggesting that the title compound may adopt non-helical conformations in solution, as observed by circular dichroism. In the crystal the molecules are hydrogen-bonded head-to-tail, forming infinitely long helical columns.
毛发毒素C末端六肽片段L-脯氨酰-L-亮氨酰-α-氨基异丁酰-α-氨基异丁酰-α-L-谷氨酰-L-缬氨醇（L-Pro-L-Leu-Aib-Aib-L-Glu-L-Valol）的晶体结构已通过X射线晶体学确定。该六肽形成一个右手3(10)-螺旋，由两个III型10原子氢键β-转角和一个I型β-转角组成。其中两个分子内氢键特别弱，因此表明该标题化合物在溶液中可能采用非螺旋构象，这与圆二色性观察结果一致。在晶体中，分子通过头对头氢键连接，形成无限长的螺旋柱。
