两个类似LARA的-核酸辅助因子利用酶的结构,具有单一的催化胺残留物
Santhosh Gatreddi1,2, Sundharraman Subramanian2, Dexin Sui2
1Department of Microbiology, Genetics, and Immunology, Michigan State University, East Lansing, Michigan, USA.
Protein science : a publication of the Protein Society
|November 13, 2025
概括
研究人员研究了缺乏关键胺残留物的LarA同类物 (LarAHs),揭示了新型的octameric结构和NPN辅因子结合的独特活性位点. 这扩大了对LarA酶机制和在碳水化合物代谢中的潜在作用的理解.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 酶学 是一种酶学.
背景情况:
- -核酸 (NPN) 辅因子对于LARA家族酶中α-酸的种族化/epimerization至关重要.
- 一种保守的质子合化物转移机制依赖于两个催化基因残留物用于酸催化.
- 一些LarA同类物 (LarAHs) 含有阿斯巴拉基尼尔残留物而不是希斯蒂丁,阻止了正规的酸催化.
研究的目的:
- 为了研究缺乏催化希斯提丁残留物的LARAHs的结构和功能.
- 阐明这些变异酶中NPN辅因子结合和基质加工的机制.
- 探索这些独特的LARAHs的进化分歧和潜在的代谢作用.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 来确定带有和没有NPN辅因子的LARAH的结构.
- 进行生物化学测试以分析基质的识别和处理.
- 基因组上下文分析被用来推断潜在的代谢途径.
主要成果:
- 对于研究的LarAHs,观察到一种新的,一致的octameric组合,在LarA家族中是前所未有的.
- 结构揭示了一组不同的活性部位残留物参与基质结合和加工与研究完善的LARAHs相比.
- 基因组分析表明这些LARAHs在碳水化合物代谢中的潜在作用.
结论:
- 这些发现揭示了LarA酶的新结构类别,其活性位点结构和组装发生了变化.
- 这些LARAH可能在NPN辅因子依赖反应中采用不同的催化机制.
- 这项研究扩大了已知的LarA酶机制的范围,并提出了新型的新陈代谢功能.
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