4-amino-4-deoxychorismate合成酶的全性通路的结构基础
Yusuke Nakamichi1, Jyumpei Kobayashi2, Koichi Toyoda2
1Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan.
Acta crystallographica. Section D, Structural biology
|September 15, 2023
概括
4-Amino-4-deoxychorismate合成酶 (ADCS) 是通过全osteric机制进行调节的. 研究人员确定了双功能酶的晶体结构,揭示了ADCS活动和调节所必需的独特二元结构.
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:
- 4-Amino-4-deoxychorismate synthase (ADCS) 是一个由PabA和PabB子单元组成的关键酶.
- ADCS通过PabA和PabB之间的全性机制调节化物利用,但由于缺乏复杂的结构,确切的机制尚不清楚.
- 了解ADCS全调节对于理解代谢途径和潜在的药物点至关重要.
研究的目的:
- 通过确定双功能酶的晶体结构来阐明ADCS的全性机制.
- 为了描述Streptomyces venezuelae PapA (SvPapA) 酶的结构和功能性质.
- 确定涉及ADCS活动和监管的关键残留物和结构特征.
主要方法:
- 进行X射线晶体学以确定SvPapA.的3D结构.
- 酶活性测定用于测量与不同基质和辅助因子的ADCS功能.
- 结构分析以确定基质结合点和构造变化.
主要成果:
- SvPapA的晶体结构揭示了一个独特的二维复合体,其中来自不同单体的PabA和PabB域形成了一个活性位点.
- Chorismate结合诱导PabB域中的结构变化,促进基质识别和催化.
- 2+结合部位和PabA域形状由化物存在来调节,这表明有动态的全调节机制.
- 在Mg2+的存在下,SvPapA使用谷氨酸或作为氨基捐赠体表现出ADCS活性.
结论:
- 这项研究揭示了功能性ADCS复合体的第一个晶体结构,为其独特的维度组织提供了原子级的洞察力.
- 结构和功能数据阐明了ADCS中的全调节的分子基础,突出显示了合力酸结合和酶构成之间的相互作用.
- 这些发现为了解体内ADCS功能和设计向抑制剂提供了基础.
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