prFMNH2结合的伴侣LpdD协助UbiD脱碳酶的激活
Deepankar Gahloth1, Karl Fisher1, Stephen Marshall1
1Manchester Institute of Biotechnology, University of Manchester, Manchester, UK.
The Journal of biological chemistry
|January 15, 2024
概括
在大肠杆菌中,UbiD酶家族需要一个伴侣蛋白质LpdD来激活. 这一发现揭示了前化黄依赖脱碳酶的多种成熟途径.
科学领域:
- 生物化学 生物化学
- 酶学 是一种酶学.
- 微生物生物化学 微生物生物化学
背景情况:
- 对于微生物代谢至关重要的UbiD酶家族利用了前化黄 (prFMN) 辅因子.
- 虽然一些UbiD酶会自我激活,但其他一些酶,如大肠杆菌UbiD,会抵抗激活,阻碍研究.
- 了解UbiD激活是探索它们充分代谢潜力的关键.
研究的目的:
- 为了研究 Escherichia coli UbiD 酶的激活机制.
- 确定使UbiD酶在体外和体内激活的因素.
- 探索UbiD酶家族中的辅因子成熟过程的多样性.
主要方法:
- 在大肠杆菌中LpdD的异质表达,以评估其对UbiD活性的影响.
- 净化和结构分析 (晶体学) 的LpdD.
- 在试验室中使用纯化的LpdD,prFMNH2和apo-UbiD.进行溶解试验.
主要成果:
- 在大肠杆菌中,LpdD的异质表达恢复了3,4-二基酸脱碳化活性.
- 结构上类似于蛋白质酶组合伴侣的LpdD,特别结合了减少的prFMNH2.
- 这种LpdD-prFMNH2复合物促进了纯化的大肠杆菌Apo-UbiD的体外激活.
结论:
- LpdD作为一个陪伴者,调解prFMNH2结合和氧化成熟以激活UbiD.
- UbiD酶成熟表现出多样性,包括超出已知的UbiX前转移酶的伴侣辅助途径.
- 仅仅UbiX的同表达不足以激活所有UbiD家族成员;陪伴者也是关键的.
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