在SepF聚合过程中形成曲率的分子基础
Wenjing Liu1,2, Chang Zhang1, Huawei Zhang3,4
1National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, People's Republic of China.
概括
像SepF这样的蛋白质组合形成了曲的结构,对细胞分裂至关重要. 这项研究表明,螺旋间接触,而不是内部序列,决定了这些必不可少的蛋白质聚合物的曲率.
科学领域:
- 结构生物学是结构生物学.
- 生物化学 生物化学
- 微生物学 微生物学
背景情况:
- 蛋白质自我组装成曲线结构对于细胞过程至关重要,包括细菌细胞分裂.
- 细菌细菌中的隔膜形成蛋白 (SepF) 聚合成均的曲率,调节隔膜厚度.
- SepF聚合涉及不同的β-β和α-α接口,但曲率形成机制尚不清楚.
研究的目的:
- 为了研究SepF聚合过程中曲率形成的机制.
- 为了比较野生类型循环SepF和线性突变 (G137突变在β-β接口上的) 之间的结构差异.
- 阐明单元间接口在控制蛋白质组合形状方面的作用.
主要方法:
- 固态核磁共振 (SSNMR) 谱学用于分析蛋白质结构.
- 电子显微镜 (cryo-EM) 用于组件的高分辨率成像.
- 计算模拟用于建模和理解结构动态.
主要成果:
- 组件内部的序列变化 (由于G137突变) 并没有显著改变组件的形状.
- 在组装单元之间的接触中介的α-α接口被确定为组装曲率的主要决定因素.
- 原子层面的分析表明,α-α接口内的α2螺旋的角度方向控制了组件曲率.
结论:
- SepF组件的曲率由单元间α-α接口控制,特别是α2螺旋的方向.
- 螺旋间接触对于保持蛋白质组合的特定曲率至关重要.
- 这项研究提供了对蛋白质自我组装和形状调节的原子洞察.
相关概念视频
00:57Cationic Chain-Growth Polymerization: Mechanism
2.3K
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the...
2.3K
01:08Molecular Weight of Step-Growth Polymers
2.2K
Step growth polymerization involves bi or multifunctional monomers. Bifunctional monomers react to form linear step growth polymers, whereas multifunctional monomers react to form non-linear or branched polymers.
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
2.2K
01:03Step-Growth Polymerization: Overview
3.5K
Step-growth or condensation polymerization is a stepwise reaction of bi or multifunctional monomers to form long-chain polymers. As all the monomers are reactive, most of the monomers are consumed at the early stages of the reaction to form small chains of reactive oligomers, which then combine to form long polymer chains in the late stages. Hence, the reaction has to proceed for a long time to achieve high molecular weight polymers.
Many natural and synthetic polymers are produced by...
Many natural and synthetic polymers are produced by...
3.5K
01:04Anionic Chain-Growth Polymerization: Mechanism
2.0K
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...
2.0K
01:17Ziegler–Natta Chain-Growth Polymerization: Overview
3.3K
Ziegler–Natta polymerization is another form of addition or chain‐growth polymerization used for synthesizing linear polymers over branched polymers. The catalyst used for polymerization is the Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, who developed it in 1953. This catalyst is an organometallic complex of titanium tetrachloride and triethyl aluminum, with the active form of the catalyst being an alkyl titanium compound. Using the Ziegler–Natta...
3.3K
01:09Radical Chain-Growth Polymerization: Mechanism
2.5K
The radical chain-growth polymerization mechanism consists of three steps: initiation, propagation, and termination of polymerization. The polymerization initiates when a free radical generated from the radical initiator adds to the unsaturated bond in the monomer. The unpaired electron of the free radical and one π electron in the unsaturated bond creates a σ bond between the free radical and the monomer. As a result, the other π electron in the unsaturated bond converts this...
2.5K