SufS-SufE复合体的结构揭示了在铁硫生物生成中驱动受保护的硫化物转移的相互作用
Rajleen K Gogar1, Nidhi Chhikara1, Minh Vo1
1Department of Chemistry & Biochemistry, The University of Alabama, Tuscaloosa, AL, 35487, USA.
bioRxiv : the preprint server for biology
|June 3, 2024
概括
SufS/SufE复合体的第一个晶体结构揭示了氨酸脱硫酶如何将硫转移到铁-硫集群组件中. 这种结构阐明了对生命至关重要的化物转移机制.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 微生物学 微生物学
背景情况:
- 铁硫 (Fe-S) 集群是生命各领域众多氧化还原反应的重要辅助因子.
- SUF途径对于Fe-S集群生物发生是必不可少的,其中囊脱硫酶 (SufS) 提供了关键的硫原子.
- SufS酶需要由SufE等转硫酶蛋白激活,以转移硫酸中间体.
研究的目的:
- 阐明SufS-SufE相互作用和硫化物转移机制的结构基础.
- 介绍一个囊脱硫酶 (SufS) 和它的激活剂 (SufE) 之间的复合物的第一个X射线晶体结构.
主要方法:
- 使用X射线晶体学来确定大肠杆菌SufS/SufE复合体的结构.
- 用位点定向突变发生法来研究蛋白质-蛋白质界面上的特定残留物的作用.
- 进行了生物化学测定,包括35S转移实验,以评估酶活性和基质处理.
主要成果:
- 晶体结构显示了SufS和SufE之间的1:1复合体,SufE与SufS的α16螺旋相互作用.
- 突变分析确定了SufE结合所必需的α16螺旋中的关键残留物.
- 发现SufE中保存的氨酸残留物 (R119) 对该酶在支持Fe-S集群生物发生中的活体活性至关重要,可能与硫化物释放有关.
结论:
- 该SufS/SufE复杂结构为受保护的硫化物转移的机制提供了原子级的洞察力.
- 这些发现强调了特定蛋白质与蛋白质相互作用和保存残留物在促进Fe-S集群组装硫转移方面的关键作用.
- 这种结构和机制的理解可以扩展到其他相关的脱硫酶系统.
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