一个不寻常的逆转结构采用了糖氨基酸纳入格拉米西丁S的氨基酸
Gijsbert M Grotenbreg1, Mattie S M Timmer, Antonio L Llamas-Saiz
1Leiden Institute of Chemistry, Gorlaeus Laboratories, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Journal of the American Chemical Society
|March 18, 2004
概括
研究人员在gramicidin S中发现了一种新的逆转,gramicidin S是一种循环抗生素. 这种由糖氨基酸驱动的结构变化会影响.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 药用化学 医学化学
背景情况:
- 格拉米西丁S是一种循环类抗生素,结构已知.
- β转是和蛋白质中的关键次要结构.
- 修改结构可以改变它们的生物活性.
研究的目的:
- 为了研究将糖氨基酸纳入格拉米西丁S.S.中的结构影响.
- 为了表征由此修改形成的新型结构图案.
- 了解特定功能组在诱导结构变化的作用.
主要方法:
- 核磁共振 (NMR) 谱学用于分析分子结构和动力学.
- 用X射线晶体学来确定高分辨率的三维结构.
- 合成以创建修改后的格拉米西丁S类似物.
主要成果:
- 一个新的逆转,取代了本地II型β转,成功诱导了格拉米西丁S.
- 酸糖氨基酸的结合是导致观察到的结构变化的原因.
- 糖部分的C3基被确定为一个关键的H键受体,调解转折形成.
- 核磁共振和X射线晶体学证实了i和i+1残留物之间胺键的翻转.
结论:
- 这项研究揭示了格拉米西丁S的新型结构修饰,这种修饰是由糖氨基酸激活的.
- C3基组的H键接受能力对于诱导逆转至关重要.
- 这一发现为的结构与活性关系以及抗生素设计的潜力提供了洞察力.
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