在阿司匹多精和伊波加类生物合成中,碳酸类 [4+2] 循环酶的演变和多样化
Matthew D DeMars1, Sarah E O'Connor1
1Department of Natural Product Biosynthesis, Max Planck Institute for Chemical Ecology, Jena 07745, Germany.
概括
植物酶的进化揭示了复杂的单烯醇化物 (MIA) 如何形成,如阿司匹多精和伊波加化物. 这项研究追溯了MIA生物合成中的关键循环酶的祖先起源和多样化.
科学领域:
- 植物生物化学和分子进化
- 自然产品的生物合成.
- 酶功能多样化的多样化
背景情况:
- 单烯醇类化合物 (MIAs) 是一组具有复杂结构的多样化植物天然产品.
- 最近已经阐明了Apocynnaceae家族中发现的aspidosperma和iboga类化合物的生物合成途径.
- 类似于 carboxylesterase (CXE) 的酶是催化MIA支架形成的关键参与者.
研究的目的:
- 研究参与MIA生物合成的循环酶的进化史和功能多样化.
- 了解底层的分子机制的区域和enantiodivergent循环添加反应.
- 通过酶合作选择探索新代谢途径的出现.
主要方法:
- 循环酶酶的遗传学分析.
- 祖先序列重建和生物化学表征.
- 合成和测试的化学酶.
- 生物合成途径的部分异构复合.
主要成果:
- 证据表明,tabersonine synthase (TS) 从一个祖先的CXE进化,其次是冠状腺素合成酶 (CorS) 和卡萨兰丁合成酶 (CS) 的出现.
- 证明由CXE类酶催化的区域和反衍生物 [4+2] 循环添加反应.
- 确定负责差异循环活动的分子变化.
- 通过招募乱交酶的阿司匹多精子类化合物的初始出现的假设.
结论:
- 这项研究提供了MIA生物合成酶的进化轨迹的见解.
- 它强调了小的序列变化和现有的酶功能的选择如何导致新代谢途径的出现.
- 这些发现与阿波西纳科家族内的阿司匹多精和伊波加类化合物的化学分类学分布一致.
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