从主要的代谢途径中选择硫载体蛋白质,用于2-thiosugar生物合成
Eita Sasaki1, Xuan Zhang2, He G Sun3
1Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, USA.
Nature
|May 13, 2014
概括
科学家们阐明了硫原子如何在自然产品中形成碳-硫键. 他们在Amycolatopsis orientalis中发现了一种灵活的硫输送系统,这对于抗生素生物合成至关重要.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 自然产品的合成自然产品的合成
背景情况:
- 硫对生命至关重要,但其纳入二次代谢产物是不太了解的.
- 主要代谢物生物合成使用由特定酶激活的硫载体蛋白质.
- 通常,这些酶和蛋白质的基因聚集在一起.
研究的目的:
- 为了研究抗生素BE-7585A.中2-thiosugar部分的生物合成.
- 为了确定参与硫合并的酶和机制.
- 要了解 Amycolatopsis orientalis.中的硫输送系统.
主要方法:
- 确定一个假定的2-硫糖糖合成酶 (BexX).
- 在Amycolatopsis orientalis.的基因组测序.
- 生物化学测试用于测试酶活性和蛋白质相互作用.
- 进行X射线晶体学以确定蛋白质结构.
主要成果:
- BexX被识别为一种2-thioglucose合成酶,类似于ThiG.
- 在BE-7585A集群中没有发现相关的硫载体蛋白质基因.
- 在A. orientalis中,单个激活酶可以修改多个硫载体蛋白质.
- X射线晶体学揭示了BexX选择性蛋白质识别的结构基础.
结论:
- 这项研究提供了第一个自然糖形成的完整描述.
- 东方性 Amycolatopsis 在初级和二级新陈代谢中使用无序的硫输送系统.
- 这些发现表明,在天然产品生物合成中,采用初级代谢中的硫机械的总体策略.
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