螺旋(腹足类)
圆二色性
两亲性
α螺旋
化学
胶原螺旋
侧链
三螺旋
立体化学
结晶学
蛋白质二级结构
氨基酸
聚合物
有机化学
生物化学
共聚物
生物
生态学
蜗牛
作者
Toshiaki Takei,Atsuhito Okonogi,Kumiko Tateno,Akiko Kimura,Shuichi Kojima,Kazumori Yazaki,Kin‐ichiro Miura
摘要
The polypeptide alpha3, which was synthesized by us to produce an amphipathic helix structure, contains the regular three times repeated sequence (LETLAKA)(3), and alpha3 forms a fibrous assembly. To clarify how the side chains of amino acid residues affect the formation of alpha helix, Leu residues, which are located in the hydrophobic surface of an amphipathic helix, were replaced by other hydrophobic aliphatic amino acid residues systematically, and the characters of the resulting polypeptides were studied. According to the circular dichroism (CD) spectra, the Ile-substituted polypeptides formed alpha helix like alpha3. However, their helix formation ability was weaker than that of alpha3 under some conditions. The Val-substituted polypeptides formed alpha helix only under restricted condition. The Ala-substituted polypeptides did not form alpha helix under any condition. Thus, it is clear that the order of the alpha helix formation ability is as follows: Leu >or= Ile > Val > Ala. The formation of alpha helix was confirmed by Fourier Transform Infrared (FTIR) spectra. Through electron microscopic observation, it was clarified that the formation of the alpha helix structure correlates with the formation of a fibrous assembly. The amphipathic alpha helix structure would be stabilized by the formation of the fibrous assembly.
科研通智能强力驱动
Strongly Powered by AbleSci AI