对NF-κB向毒素AIP56的膜相互作用和转位的非传统结构和机制
Johnny Lisboa1,2, Cassilda Pereira3,4, Rute D Pinto3
1Fish Immunology and Vaccinology Group, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135, Porto, Portugal. johnny.lisboa@i3s.up.pt.
Nature communications
|November 17, 2023
概括
细菌的AB毒素使用独特的三域结构进入细胞并发挥作用. 这项研究揭示了AIP56的存在.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 毒理学 毒理学 毒理学
背景情况:
- 细菌的AB毒素是宿主细胞内部化的关键毒性因素.
- 这些毒素通过内细胞分裂将酶域转移到细胞质中.
- 原型毒素具有不同的受体结合和转位域.
研究的目的:
- 为了阐明细菌AB毒素AIP56.6的三维结构.
- 描述AIP56.6的域组织和转移机制.
- 将AIP56的结构和功能与原型AB毒素进行比较.
主要方法:
- 对AIP56.5的三维结构确定.
- 对域组织和功能元素的分析.
- 与已知的AB毒素结构和机制进行比较.
主要成果:
- AIP56表现出三种域结构:催化,中间和受体结合域.
- 与预期相反,AIP56缺乏一个独特的,复杂的转移域.
- 转位元素分布在AIP56的域中,在催化域中使用螺旋式发针.
结论:
- AIP56采用一种新的,去中心化的毒素转移机制.
- 内体酸性化触发了膜插入和孔隙形成的形状变化.
- 催化,中间和受体结合域共同介导孔隙形成.
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