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Synthesis of an Intein-mediated Artificial Protein Hydrogel
Published on: January 27, 2014
一个烯酸酸酶模型复合物的第一个例子,可逆地结合烯酸
Jason Shearer1, Henry L Jackson, Dirk Schweitzer
1Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195, USA.
Journal of the American Chemical Society
|September 19, 2002
概括
亚酸酶 (NHase) 模型显示,铁 (III) 可以结合亚酸,这表明亚酸转换的机制. 这项研究揭示了NHase类铁环境中的烯结合偏好和联结物交换动态.
科学领域:
- 生物有机化学 生物有机化学
- 酶的机制 酶的机制
- 有机金属化学 有机金属化学
背景情况:
- 酸酸酶 (NHase) 催化酸转化为胺,但其机制尚不清楚.
- 一种拟议的机制涉及水对结合铁的烯酸进行核友性攻击.
- 了解NHase的活性部位对于阐明其催化功能至关重要.
研究的目的:
- 合成和表征一个模仿NHase活性位点环境的铁 (III) 复合体.
- 为了研究利和其他配体与模型复合物的结合.
- 通过研究连接体结合和交换动力学,阐明化的机械学方面.
主要方法:
- 合成一个五坐标的铁 (III) 复合体, [Fe (III) (S) (2) (Me) N (III) (Et,Pr)) ] (+).
- 射线吸收光谱 (XAS) 用于研究复杂的形成.
- 可变温度电子吸收光谱和13CNMR线路扩展分析用于热力学和动力学研究.
主要成果:
- 模型复合物可逆地结合烯酸,醇,氨基和硫酸盐.
- XAS证实了与甲醇和酸反应时形成的六坐标复合物.
- 竞争性结合研究表明,亚烯优先结合于酒精,这表明它们可以从铁位点取代水.
- 确定了烯和二烯结合/交换的热力学和动力学参数,揭示了铁 (III) 中心的显著可变性.
结论:
- 这项研究提供了第一个证据,表明铁在类似NHase的环境中可以形成稳定的化复合物.
- 观察到的连接物交换率表明,低旋转铁在这种环境中比预期的更不稳定.
- 铁协调球中的轻微带诱导的扭曲显著影响金属复合物的反应性.
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01:28Structures of Carboxylic Acid Derivatives
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