新发现的Photorhabdus laumondii瘤坏死因子-类似于莱克的结构和功能特征
Filip Melicher1,2, Pavel Dobeš2,3, Jan Komárek1,2
1Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic.
The FEBS journal
|October 17, 2025
概括
瘤亡因子 (TNF) 类似的莱克 (PLTL) 结合特定的分支寡糖. 结构分析揭示了一个独特的六边形形,表明在Photorhabdus-nematode共生中发挥了作用.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 葡萄糖生物学 葡萄糖生物学
背景情况:
- 菌细菌和菌线虫形成共生关系,充当昆虫病原体.
- 莱克是Photorhabdus产生的糖结合蛋白,对于宿主-共生体相互作用至关重要.
- 瘤坏死因子 (TNF) 类莱克 (PLTL) 是一种新发现的莱克,其序列与人类的BC2L-C莱克相似.
研究的目的:
- 在结构和功能上描述PLTL.
- 为了确定PLTL的糖结合特异性.
- 为了阐明PLTL在Photorhabdus-nematode共生中的作用.
主要方法:
- 甘氨酸阵列分析和表面等离子体共振 (SPR) 以确定结合偏好.
- 蛋白质结晶学以确定PLTL的复杂结构与BLe b糖.
- 质谱学和分析超离心法来描述PLTL的四分体结构.
主要成果:
- PLTL表现出与分支组织血液组寡糖的特定结合.
- 晶体结构显示了PLTL与BLe b糖化合物复合,详细说明了稳定关键甘氨酸部分的键.
- PLTL形成了一个独特的六合体结构,由分子间的二硫化物桥梁稳定.
- 质谱法和分析超离心法证实了六米结构.
结论:
- PLTL 具有复杂的甘氨酸特异性,用于分支基因组血型小糖.
- 结构和功能数据表明,PLTL的主要作用在于互惠的Photorhabdus-nematode关系,而不是昆虫相互作用.
- PLTL代表了一种新的类似TNF的莱克,在基于甘氨酸的诊断和生物技术中具有潜在的应用.
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