基质耐受性兰西合成酶ProcM循环的动态分析
Emily K Desormeaux1, Garrett J Barksdale2, Wilfred A van der Donk1,2,3
1Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
ACS catalysis
|December 26, 2024
概括
基质序列显著影响ProcM产生的兰氏的最终环形状,ProcM是一种II类兰氏合成酶. 动力学研究表明,对序列的修改会改变反应速率,导致不同的环结构.
科学领域:
- 生物化学 生物化学
- 自然产品的合成自然产品的合成
背景情况:
- 兰氏是一种通过核糖体合成和转化后修饰的 (RiPPs),具有 thioether 交叉链.
- 像ProcM一样的II类兰氏合成酶是对形成这些复杂的宏循环结构至关重要的双功能酶.
- ProcM具有广泛的基质耐受性,可以创建多种类型的库.
研究的目的:
- 调查ProcM催化兰西合成中最终环形模式的决定因素.
- 了解基质序列变化的影响,对动力学和结果的lanthipeptide修改.
- 使用孤立修改步骤的速率来评估最终环形图案的可预测性.
主要方法:
- 用动力测试来分析ProcM催化ProcA3.3的修饰及其序列变异.
- 测量和比较了单个环形的反应速率.
- 研究了氨基酸替代 (Ser到Thr,反之亦然) 对环形模式的影响.
主要成果:
- 基质序列的改变导致反应速率的变化,导致不同的修饰顺序和最终环形状.
- 随着的成熟,连续反应的速率下降,观察到的速率常数表明了固有的酶活性.
- 孤立修改的速率可以预测最终的环形模式,尽管确定了一些局限性.
- 意想不到的是,Ser和Thr残留物的相互转换也改变了环形图案.
结论:
- 基质序列是ProcM产生的兰氏中最终环形模式的主要决定因素.
- 孤立修饰的动态分析为兰氏环模式提供了一个预测工具,具有已知的局限性.
- 即使是微妙的序列变化,如Ser/Thr相互转换,也可以显著影响循环化结果.
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