在草生物合成中的双重功能酸环酶的表征
Garret M Rubin1, Krishna P Patel2, Yujia Jiang1
1Department of Medicinal Chemistry, Center for Natural Products, Drug Discovery and Development, University of Florida, Gainesville, Florida 31610, United States.
ACS chemical biology
|December 4, 2024
概括
研究人员通过使用ATP-抓取酶PruA和PruB阐明了Prunipeptin的生物合成,prunipeptin是11组的草胺. 这项研究揭示了对双重宏循环化的关键机制性见解,有助于未来的酶工程.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 酶学 是一种酶学.
背景情况:
- Graspetides 是通过核糖体合成的,具有由ATP-grasp酶形成的复杂的宏循环结构.
- 像普鲁尼平素这样的11组草类药物,既具有麦克罗拉克和麦克罗拉克的交叉链,需要双重的宏环化.
- 参与双重宏循环的ATP-抓取酶的机制细节在很大程度上仍未被描述.
研究的目的:
- 为了重建和研究从*Streptomyces coelicolor**中得到的普鲁尼佩的生物合成.
- 阐明PruA和PruB ATP捕获宏环酶的酶机制.
- 为了获得对这些酶的结构-功能关系的洞察力,为潜在的工程.
主要方法:
- 使用重组PruA和PruB宏循环酶重建普鲁尼平的生物合成.
- 对PruB酶活性进行动态分析,包括确定像*k*cat这样的动态参数.
- 进行X射线晶体学以确定PruB的结构和局部定向突变发生以确定关键残留物.
- 对PruA/PruB共复合体进行计算建模,以了解基质相互作用.
主要成果:
- 普鲁B的酶动力学与其他草类循环酶相比,具有增强的催化效率,可能是由于ATP再生系统.
- 普鲁B的X射线晶体结构显示出独特的特征,使其与1组和2组ATP捕获酶区别开来.
- 位点定向突变发生证实了特定残留物的重要性,包括保存的DxR动机,对于PruB的催化功能.
- 计算建模表明了一种序列机制,PruB可能会在PruA上启动麦克罗拉克顿的形成.
结论:
- 这项研究为参与11组草酸生物合成的ATP捕获酶PruA和PruB提供了重要的机械洞察力.
- 这些发现增强了对通过ATP-抓取酶介导的双重宏循环化过程的理解.
- 详细的结构和机制信息为设计这些酶用于新型生物技术应用提供了基础.
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