在Saccharinae草的区域选择性stilbene O-甲基化
Andy C W Lui1,2, Kah Chee Pow3, Nan Lin1
1School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong, China.
Nature communications
|June 12, 2023
概括
糖草草自然产生O-甲基化 stilbenes,有价值的营养品. 研究人员确定了特定的酶,stilbene O-methyltransferases (SOMTs),以及它们的区域选择性O-甲基化结构基础,使生物工程潜力成为可能.
科学领域:
- 植物生物化学 植物生物化学
- 酶学 是一种酶学.
- 代谢工程是代谢工程.
背景情况:
- 甲基化O-stilbenes是受欢迎的营养药物,但通常不是由作物合成的.
- 糖草具有产生这些有价值化合物的内在能力.
研究的目的:
- 为了研究在Saccharinae草中O-甲基化的酶机制.
- 识别和描述负责固醇和异胺原蛋白生物合成的特定酶.
- 阐明斯蒂尔本O-甲基转移酶 (SOMTs) 和咖啡酸O-甲基转移酶 (COMTs) 的不同基质特异性的结构基础.
主要方法:
- 对 SOMT 和 COMT 酶的遗传学分析.
- 重组酶测试以确定催化活性和区域选择性.
- 通过X射线晶体学来确定SbSOMT和SbCOMT与矿复合体中的结构.
- 位点定向突变发生,以确定影响基质结合和区域选择性的关键残留物.
主要成果:
- 一种斯蒂尔O-甲基转移酶 (SbSOMT) 被确定为在中的斯特洛斯蒂尔生物合成必不可少的.
- SbSOMT和COMT表现出明显的区域选择性,分别甲基化 stilbenes 的 A 环和 B 环.
- 结构分析显示,SbSOMT (Ile144/Phe337) 中的特定疏水性残留物对A环甲基化至关重要,与SbCOMT (Asn128/Asn323) 中的残留物相比,有利于B环甲基化.
- 一种保存的COMT涉及到甘中异胺原蛋白的形成.
结论:
- 糖草是一种多种O-甲基化 stilbenes 的天然来源.
- 鉴定的SOMT和COMT基于关键氨基酸残留物具有可预测的区域选择性.
- 这种理解为生物工程在作物中的新型O-甲基化 stilbenes 提供了基础.
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