对独特的五环三合成酶TwOSC的结构和催化洞察力
Yunfeng Luo1, Xiaoli Ma2, Yufan Qiu3
1School of Traditional Chinese Medicine, Capital Medical University, Beijing, 100069, China.
Angewandte Chemie (International ed. in English)
|October 16, 2023
概括
这项研究揭示了植物friedelin合成酶 (TwOSC) 的结构,揭示了复杂friedelin生物合成背后的机制. 确定了关键的残留物,使得突变设计能够提高三烯产量.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 植物科学 植物科学
背景情况:
- 氧化二烯循环酶 (OSCs) 催化复杂的循环,形成多种五环三烯酸 (PTs).
- 弗里德林生物合成涉及一个独特的九阶段阴离子穿运行 (CSR) 级联,但由于缺乏结构数据,其机制和植物OSCs的作用仍然不清楚.
研究的目的:
- 阐明Friedelin生物合成中CSR级联的结构基础和催化机制.
- 通过植物OSCs识别参与PT骨架形成的关键氨基酸残留物.
主要方法:
- 确定了Tripterygium wilfordii Hook的冷电子显微镜结构. f氧化二烯环酶 (TwOSC).
- 执行量子力学/分子力学 (QM/MM) 模拟,以分析CSR级联能量配置文件.
- 采用理性突变发生法来设计TwOSC变体.
主要成果:
- 获得了第一个植物OSC (TwOSC) 的低温电子显微镜结构.
- QM/MM模拟揭示了CSR级联的能量概况,并确定了PT形成的关键残留物.
- 半导体设计的TwOSC突变体显示出显著改善了friedelin和β-amyrin的产量.
结论:
- 这项研究提供了关于植物OSC介导的friedelin生物合成和CSR机制的第一个结构性见解.
- 确定了关键残留物及其在催化复杂的三类骨架形成中的作用.
- 证明了工程OSCs的潜力,以增强有价值的三烯酸的生产.
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