生物活性酸的胺基化:丁糖氨酸α-基化单氧基酶的结构
S T Prigge1, A S Kolhekar, B A Eipper
1Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 21205, USA.
Science (New York, N.Y.)
|November 21, 1997
概括
丁糖氨酸α-amidating单氧酶 (PAM) 对于激素活性至关重要. 对其PHM域的结构研究揭示了涉及铜激活氧的机制,为多巴胺β-单氧酶提供了洞察力.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- 许多神经和激素需要C-终端化以获得生物活性.
- 基甘氨酸α-胺基化单氧酶 (PAM) 是催化这种必要的翻译后修饰的关键酶.
- PAM的N终端域,丁糖氨酸α-氧化单氧酶 (PHM),含有铜离子,对于其催化功能至关重要.
研究的目的:
- 为了阐明氧化大鼠PHM的催化核心的结构.
- 为了研究基质结合后的结构变化.
- 为了获得对PHM反应机制的机械洞察力.
主要方法:
- 使用X射线晶体学来确定氧化老鼠PHM的结构.
- 来自内源铜离子的异常信号有助于结构的确定.
- 在缺乏和存在绑定基质的情况下解决了结构.
主要成果:
- 确定了氧化大鼠PHM的晶体结构.
- 结构数据揭示了酶的催化核心.
- 这些结构表明反应机制涉及基板激活由一个铜结合的氧物种.
结论:
- 确定的结构为PHM反应提供了重要的机制和结构洞察力.
- 这些发现表明了一种涉及铜激活氧物种的新型机制.
- 这些见解直接适用于理解相关的酶,多巴胺β-单氧酶.
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