人体肠道的铁盗窃的结构基础
Augustinas Silale1, Yung Li Soo1, Hannah Mark1
1Biosciences Institute, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, United Kingdom.
bioRxiv : the preprint server for biology
|September 2, 2025
概括
菌体使用XusABC系统从病原体中窃取铁. 结构研究揭示了这种异体吸收系统的功能,突出了其广泛的异体运输能力.
科学领域:
- 微生物学
- 结构生物学
- 生物化学
背景情况:
- 铁对于微生物生长至关重要,但在宿主环境中通常很稀缺.
- 细菌利用 siderophores 进行结合和运输铁.
- 病原体和共生生物在肠道微生物群中争夺铁.
研究的目的:
- 通过*Bacteroides thetaiotaomicron* XusABC系统来阐明异体吸收的分子机制.
- 确定异体识别和运输的结构基础.
- 评估XusABC系统的基板范围.
主要方法:
- 确定XusAB复合物的晶体结构.
- 低温电子显微镜 (cryo-EM) 分析
- 生物化学测定以评估 siderophore 的结合和运输.
主要成果:
- 晶体和冷EM结构揭示了XusB脂蛋白如何识别与铁结合的异体.
- 这些结构详细介绍了XusB与XusA TonB依赖转运器之间的相互作用.
- 类同类物有能力运输具有不同铁化群的多种 siderophores.
结论:
- XusABC 系统提供了肠道中铁盗窃的详细分子机制.
- 结构洞察力解释了异体的识别和转移.
- 该系统的广泛基质特异性表明它在微生物之间的铁竞争中起着重要作用.
相关概念视频
Microbial Nutrition
287
Organisms exhibit remarkable metabolic diversity, categorized based on how they acquire energy and carbon. These strategies enable survival in various ecological niches and are essential for maintaining energy flow and nutrient cycling within ecosystems.Energy and Carbon SourcesOrganisms are classified as phototrophs or chemotrophs based on energy acquisition. Phototrophs use light as their energy source, while chemotrophs rely on oxidizing chemical compounds. Further differentiation arises...
287
Bacterial Phylum Bacteroidota
121
The phylum Bacteroidota includes over 700 species classified into four primary orders: Bacteroidales, Cytophagales, Flavobacteriales, and Sphingobacteriales. These gram-negative, non-sporulating rods exhibit saccharolytic capabilities and can be aerobic or fermentative, encompassing obligate aerobes, facultative aerobes, and obligate anaerobes. Many species display gliding motility, though some are nonmotile or use flagella. The genus Bacteroides is well-studied due to its significant role in...
121
Bacterial Phylum Proteobacteria
131
Proteobacteria, one of the largest and most diverse bacterial phyla, encompasses a wide range of Gram-negative bacteria distinguished by their outer membrane composed of lipopolysaccharides. These microorganisms exhibit various metabolic capabilities, including phototrophy, chemolithotrophy, and heterotrophy, and thrive in diverse environments from soil to aquatic systems and host-associated niches. The phylum is divided into six classes: Alphaproteobacteria, Betaproteobacteria,...
131
Bacterial Phylum Firmicutes
144
Firmicutes is a diverse phylum of Gram-positive bacteria characterized by a low GC content in their genomes. This phylum includes organisms with monoderm or diderm cell envelopes, highlighting a complex evolutionary history. Firmicutes comprises several major orders, including Lactobacillales, Clostridiales, and Bacillales, which exhibit remarkable diversity in their morphology, metabolism, and ecological roles.The order Lactobacillales includes lactic acid bacteria, which are fermentative...
144
Other Unique Bacteria
82
Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic...
82
Bacterial Flora of the Large Intestine
641
The gut microbiome is formed by a vast and diverse community of bacteria that colonizes our large intestine. These bacteria start residing in the gut from birth and continue diversifying throughout life, influenced by factors such as diet, lifestyle, and stress. The gut bacterial community also includes bacteria from food and those that enter the colon through the anus.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
641


