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来自根的氧化和减少的星素的晶体结构
Michael Koch1, Milko Velarde, Mark D Harrison
1Abteilung Strukturforschung, Max-Planck-Institut für Biochemie, Am Klopferspitz 18, D-82152 Martinsried, Germany.
Journal of the American Chemical Society
|January 6, 2005
概括
植物铜素的乌米亚宁 (UMC) 的晶体结构已经确定. 它独特的表面特征和活性位点表明它在蛋白质间电子转移中起作用.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 蛋白质科学 蛋白质科学
背景情况:
- 乌米亚宁 (UMC) 是一种1型铜蛋白,属于植物的恒星子类.
- 植物素是一种无处不在的植物毒素家族,参与电子转移.
研究的目的:
- 为了确定氧化 (Cu(II)) 和减少 (Cu(I)) umecyanin 的晶体结构.
- 阐明乌米亚宁在电子转移中的作用的结构基础.
主要方法:
- 使用X射线晶体学以高分辨率 (1.9和1.8A) 确定Cu(II) 和Cu(I) UMC的结构.
- 在氧化和还原形式之间对活性部位和表面特征进行比较分析.
主要成果:
- 总体而言,UMC的折叠与其他植物素相似.
- 活动部位的特点是Cu (II) 的扭曲四面体几何和Cu (I) 的三角形金字塔几何.
- 在活性部位附近,UMC缺乏疏水性斑块,但具有很大的表面酸性斑块,使其与其他毒素区别开来.
结论:
- 在氧化还原变化时,在活性位点发生有限的结构变化,类似于带有轴性Met联结体的1型铜位点.
- 独特的表面特征和活性部位结构表明,乌米亚宁在蛋白质间电子转移中起着作用.
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