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变异性支持对模块化聚基酸合成酶乙烯载体蛋白如何与下游合成酶对接的AlphaFold预测

Melissa Hirsch¹, Ronak R Desai², Shreyas Annaswamy²

¹Department of Chemistry, The University of Texas at Austin, Austin, Texas, USA.

|July 30, 2024

概括

聚基化合成酶 (PKS) 域通过乙载体蛋白 (ACP) 和合成酶 (KS) 相互作用来对接. AlphaFold-Multimer揭示了KS活性部位的新型β-转变形状,这对多基基生物合成至关重要.

科学领域:

生物化学生物化学
结构生物学结构生物学
分子生物学分子生物学

背景情况:

聚化合成酶 (PKS) 是大型的多域酶,负责合成各种聚化天然产品.
精确的多基基链延长依赖于精确的域-域相互作用,特别是乙载体蛋白 (ACP) 和合成酶 (KS) 域的对接.
交换,即从ACP转移到KS的生长的多基基链,是由域相互作用调节的关键步骤.

研究的目的:

预测和描述PKS中ACP和KS领域之间的结构界面.
调查特定的KS形状在调节多基化生物合成过程中的交易化中的作用.
通过现场定向突变发生,通过实验验证预测的ACP-KS相互作用接口.

主要方法:

使用AlphaFold-Multimer进行了ACP-KS复杂结构的in silico预测.
分析预测的结构,以保存交互动图案和域定向.
在模型PKS的KS域内对关键残留物进行了位点定向的突变发生.
测试了野生类型和突变PKS酶的酶活性.

主要成果:

AlphaFold-Multimer预测了ACP-KS交易控制点的一般接口.
观察到KS图案TxLGDP的两个不同的构造:一个α-螺旋转和一个新的β-转.
贝塔转变形状与更开放的KS活性部位和ACP和KS催化残留物之间的更近距离有关.
突变性研究证实了预测界面残留对PKS活性的重要性.

结论:

这项研究揭示了KS活性部位的新型β转变形态,可能有助于转基因.
预测的ACP-KS接口为了解PKS中的基质选择和转移提供了结构基础.
实验验证支持域对接的拟议模型,并突出了参与调节多基基生物合成的关键残留物.

关键词:

阿尔法折叠是什么意思阿尔法折叠乙载体蛋白质是一种乙载体蛋白质.域名域名接口基因合成酶 (ketosynthase) 是一种酶.模块化多基化合成酶.

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