通过平行轨迹在酶的进化中出现的机械形状和基质选择性概况
Christos S Karamitros1,2, Kyle Murray3,4, Yoichi Kumada5
1Department of Chemical Engineering, University of Texas at Austin (UT Austin), Austin, TX, USA.
Nature communications
|August 16, 2024
概括
实验室进化创造了不同的人类 kynureninase (HsKYNase) 酶. 尽管活动相似,但它们表现出不同的结构动力学和机制,揭示了对酶进化的洞察力和通用主义者与专业主义者的特征.
科学领域:
- 生物化学 生物化学
- 酶工程是什么? 酶工程是什么?
- 进化生物学 进化生物学
背景情况:
- 实验室进化可以产生具有改变基质特异性的独特酶.
- 了解这些进化的酶是否具有共同的融合形态动力学和机制至关重要.
- 人类 kynureninase (HsKYNase) 是一个相关的模型,特别是在癌症免疫治疗中.
研究的目的:
- 调查基因上不同,进化HsKYNase变体的结构动态和机制特征.
- 要比较一个专家酶 (HsKYNase_66) 和一个通用酶 (HsKYNase_93D9) 通过不同的轨迹进化.
- 阐明进化途径与酶功能之间的关系.
主要方法:
- 实验室进化产生不同的hsKYNase变体 (hsKYNase_66和hsKYNase_93D9).
- 在稳定状态前进行动态分析,以确定催化参数和机制.
- -交换质谱法 (HDX-MS) 用于探测形态动力学.
主要成果:
- HsKYNase_66进化了高Kynurenine (KYN) 活性,而HsKYNase_93D9进化了可比的KYN活性和对3'-hydroxykynurenine (OH-KYN) 的普遍接受.
- 动态分析表明,与野生类型相比,HSKYNase_66的速率决定步骤发生了变化,但HSKYNase_93D9的机制保留了.
- HDX-MS 显示了 HsKYNase_66 和 HsKYNase_93D9 之间明显的构造动态,与原生细胞的正义基因不同.
结论:
- 进化的专家和通用酶,即使具有相似的催化改进,也可以具有不同的结构动力学和机械基础.
- 这项研究为将进化轨迹与酶的功能性和动态性质联系起来提供了一个框架.
- 这些发现有助于理解酶适应和工程对于特定应用,如癌症免疫疗法.
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