在治疗生物合成中的o-硫化之前的多基酸脱碳化链终结
Liangcai Gu1, Bo Wang, Amol Kulkarni
1Life Sciences Institute, Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Journal of the American Chemical Society
|October 20, 2009
概括
研究人员在curacin A生物合成中发现了一种新的脱碳酶化链终结机制. 这一过程涉及硫转移酶和铁酶酶,导致天然产品中罕见的终端烯酸.
科学领域:
- 自然产品生物合成 自然产品生物合成
- 酶学 是一种酶学.
- 海洋天然产品 海洋天然产品
背景情况:
- 生物合成创新依赖于将新基因和酶集成到新陈代谢途径中.
- 库拉A,一种抗癌,是由海洋蓝菌Lyngbya majuscula.衍生出来的.
- 聚基化合成酶 (PKS) 是大型的多酶复合体,负责生产聚基化天然产品.
研究的目的:
- 为了阐明在库拉A生物合成中前所未有的脱碳氧化链终结机制.
- 在生物化学上描述库拉辛A PKS (CurM) 内的不寻常的链终结模块.
- 为了研究硫酸转移酶 (ST) 和硫酸酶 (TE) 域在终结过程中的作用.
主要方法:
- 在CurM酶内对ST和TE催化域的生物化学表征.
- 对多基基链延长中间体和最终代谢物的分析.
- 酶测试以确定个别域的功能及其相互作用.
主要成果:
- 证实了铁酶 (TE) 域可催化聚基酸中间体的水解释放.
- 一个硫转移酶 (ST) 域在水解之前选择性地硫化 (R) - - - - - - - - - - 基组.
- 这种硫化事件触发了脱碳氧化消除,在库拉A中产生了罕见的终端烯.
结论:
- 在库拉A生物合成中发现了一种新型的脱碳氧化链终结机制,涉及连续的硫化和水解.
- 这些发现揭示了一种独特的酶策略,用于在天然产品中产生终端烯酸.
- 这项研究扩大了我们对聚基酸合成酶酶机制中的多样性和创新的理解.
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