非对称的架构和Treponema鞭毛的适应
bioRxiv : the preprint server for biology
|February 9, 2026
概括
螺旋虫通过鞭毛体使用独特的抽机机动性. 这项研究揭示了它们的鞭毛的不对称的核心结构,这对于像Treponema denticola这样的病原体的有效推进至关重要.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 生物物理学的生物物理.
背景情况:
- 螺旋虫具有独特的螺旋机运动性.
- 这种移动性是由超的配置中的周等离子体鞭毛驱动的.
- 这种推进的结构基础尚不清楚.
研究的目的:
- 为了确定超绕的鞭毛发光线的组装和适应原理.
- 阐明螺旋体机动性的结构基础.
- 为了研究鞭状结构在Treponema denticola病变发生中的作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 是一种电子显微镜.
- 低温电子断层扫描 (cryo-ET) 是一种电子断层扫描.
- 基因和生物化学分析.
主要成果:
- 确定了鞭毛丝的近原子结构.
- 一个糖化鞭毛蛋白 (FlaB) 核心被一个不对称的外包围着.
- 盖子包括一个主要蛋白质 (FlaA) 和四个小蛋白质 (FlaA1,FlaA2,FlaAP1,FlaAP2).
- 核心和外之间的特定接口对于运动性至关重要.
结论:
- 鞭状核和的协调不对称组装是螺旋体运动的基础.
- 这种组织的破坏会损害力传递和运动能力.
- 这一发现为螺旋体推进的机制提供了洞察力.
相关概念视频
Flagella and Motility in Bacteria
3.0K
Flagella are specialized, thread-like structures that extend from a bacteria's cell envelope. They play a crucial role in motility and chemotaxis. Their structural organization and functioning exemplify sophisticated biological engineering, enabling bacterial survival and adaptability in diverse environments.Structure of the FlagellumA bacterial flagellum consists of three key components: the filament, the hook, and basal body. The filament, a long, helical structure composed of repeating...
3.0K
Rotation of Asymmetric Top
1.6K
By definition, a spherically symmetric body has the same moment of inertia about any axis passing through its center of mass. This situation changes if there is no spherical symmetry. Since most rigid bodies are not spherically symmetric, these require special treatment.
The relationship between the angular momentum of any rigid body and its angular velocity, both of which are vectors, involves the moment of inertia. The moment of inertia is a scalar quantity only for spherically symmetric...
The relationship between the angular momentum of any rigid body and its angular velocity, both of which are vectors, involves the moment of inertia. The moment of inertia is a scalar quantity only for spherically symmetric...
1.6K
Asymmetric Lipid Bilayer
9.9K
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
9.9K
Polymer Classification: Architecture
3.9K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
3.9K
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.9K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.9K
Natural Selection and Adaptation
1.4K
Natural selection, a fundamental concept in evolutionary biology, is the mechanism by which evolution is driven, favoring organisms that are best adapted to their environments. This process enhances their chances of survival and reproduction. Adaptation, a key outcome of this process, involves genetic modifications that optimize an organism's functionality under specific environmental challenges, such as extreme cold or thinner air at high altitudes.
Beyond physical adaptations,...
Beyond physical adaptations,...
1.4K


