4-基烯-4-基烯的4S二聚体的异常
Matthew D Shoulders1, Frank W Kotch, Amit Choudhary
1Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Journal of the American Chemical Society
|August 5, 2010
概括
氨酸残留物上的基组的配置对蛋白质结构产生了重大影响. 将 (2S,4S) -4-基 (hyp) 隔离体纳入原蛋白模型显示出独特的结构性质和稳定性.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 蛋白质化学 蛋白质化学
背景情况:
- 4-基酶在像原蛋白这样的蛋白质中将 (Pro) 残留物修改为 (2S,4R) -4-基 (Hyp).
- 这种修改强制执行一个C (gamma) -exo环,稳定了原三环螺旋.
- 在蛋白质中没有观察到 (2S,4S) -4-基 (hyp) 隔离体.
研究的目的:
- 为了研究将hyp diastereomer纳入原体模型系统的效果.
- 了解与Hyp相比,Hyp如何影响蛋白质结构和稳定性.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 谱学和结晶学. 谱学和结晶学.
- 在原模型系统上进行热量测量研究.
主要成果:
- 的4S-基化强制形成一个C () -endo环.
- 在hype中,一个跨环状键扭曲了典型的主链扭转角度,并稳定了先前的键.
- 将hyp转化为 (2S,4S) -4-甲基 (mop) 的O-甲基化消除了这种键,恢复了标准的C(gamma) -endo,并增加了原三环螺旋的稳定性.
结论:
- 素残留物上的基组的立体化学配置对蛋白质结构和稳定性至关重要.
- 低 diastereomer 赋予独特的结构和形状性质的原体模型.
- Mop残留物比hyp残留物更多地增强了原三环稳定性,强调了基组配置的重要性.
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