在TPQ辅因子生物发生过程中捕获dopaquinone中间体,用于来自Arthrobacter globiformisis的含铜氨基氧化酶中
Robyn H Moore1, M Ashley Spies, Matthew B Culpepper
1Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA.
Journal of the American Chemical Society
|August 25, 2007
概括
这项研究证实了多帕金在多帕金 (TPQ) 生物发生过程中的中间体,并表明其可移动性. 这一发现支持多巴基在 lysine tyrosylquinone (LTQ) 在 lysyl oxidase (LOX) 内的生物发生中的作用.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 结构生物学 结构生物学
背景情况:
- 铜胺氧化酶 (CAO) 生物发生涉及自我催化,铜和氧.
- 在TPQ形成过程中提出了一种多帕金中间体,然后进行氧化.
- lysyl氧化酶 (LOX) 使用氨酸氨酸 (LTQ) 辅因子.
研究的目的:
- 为了研究 Arthrobacter globiformis CAO (AGAO) 中TPQ辅因子的生物发生.
- 阐明中间体在辅因子形成中的作用和性质.
- 探索辅因子成熟的结构基础.
主要方法:
- 局部定向的突变发生产生D298K-AGAO.
- 用X射线结晶学测定D298K-AGAO的结构,分辨率为1.7Å.
- 紫外线/Vis和共振拉曼光谱仪用于监测反应动力学.
主要成果:
- 在Lys298和dopaquinone衍生物之间形成了一种共价连接,被确定为lysine tyrosylquinone iminoquinone tautomer (LTI).
- 光谱分析证实,在LTI形成之前,有一个类似LTQ的中间体.
- 多巴金中间体在活性部位内表现出移动性.
结论:
- 这项研究证实了TPQ生物发生过程中存在多巴诺中间体的存在.
- 它在LTQ生物发生过程中为类似的多帕金中间体提供了强有力的支持.
- 突出了多巴基中间体的流动性,表明其在辅因子形成中的动态作用.
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