在二维系统中确定立体选择性的相互作用――22-基胆固醇表层的案例
Anna Chachaj Brekiesz1, Jan Kobierski2, Anita Wnętrzak1
1Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, Kraków 30-387, Poland.
The journal of physical chemistry. B
|December 17, 2024
概括
立体化学决定了细胞膜中的氧的行为. 不同的22-基胆固醇表达体现出不同的单层性质和相互作用,影响膜结构.
科学领域:
- 生物化学和生物物理学
- 膜生物学 膜生物学
- 物理化学 物理化学
背景情况:
- 氧化胆固醇衍生物 (氧醇) 对生物膜功能至关重要.
- 与许多生物分子不同,一些氧醇存在于具有不同生物效应的立体异构体中.
- 这种类型的立体同位素是22-基胆固醇 (22-OH) 体,即22(R) -OH和22(S) -OH.
研究的目的:
- 为了研究22(R) -OH和22(S) -OH表皮的独特特性.
- 为了检查它们在空气/水接口上的Langmuir单层中的行为.
- 了解立体化学如何影响氧醇与斯芬戈美林 (SM) 的相互作用.
主要方法:
- 在空气/水界面上形成的兰木尔单层.
- 表面测量仪用于异热度测量.
- 乳房角显微镜 (BAM) 用于薄膜纹理分析.
- 分子动力学 (MD) 模拟用于结构和相互作用洞察力.
主要成果:
- 22 (((S) -OH形成了凝聚的,均的单层,具有高的崩压力.
- 22(R) -OH形成了扩展,无序的单层,崩塌压力低,表现出温度依赖的域共存.
- 这两种epimers与sphingomyelin的相互作用类似,但由于立体化学驱动的结合,膜组成不同.
结论:
- 氧固醇的立体化学反应极大地影响了它们的物理特性和膜组织.
- 由于22(R) -OH的水分含量较大,这有助于其结构的可变性.
- 立体特异性键控制了22-OH表层与像SM这样的膜脂质的差异性相互作用.
更多相关视频
13:05Enzymatic Synthesis of Epoxidized Metabolites of Docosahexaenoic, Eicosapentaenoic, and Arachidonic Acids
Published on: June 28, 2019
8.0K
10:17Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
6.9K
相关概念视频
02:33Stereoisomerism of Cyclic Compounds
8.7K
In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
8.7K
02:32Stereoisomers
12.4K
On the basis of mirror symmetry, stereoisomers of an organic molecule can be further classified into diastereomers and enantiomers. Diastereomers are stereoisomers that are not mirror images of each other. Substituted alkenes, such as the cis and trans isomers of 2-butene, are diastereomers, as these molecules exhibit different spatial orientations of their constituent atoms, are not mirror images of each other, and do not interconvert. Here, the interconversion is suppressed due to...
12.4K
02:05Prochirality
3.8K
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
3.8K
02:24Properties of Enantiomers and Optical Activity
16.7K
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
16.7K
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
8.3K
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
8.3K
02:43E2 Reaction: Stereochemistry and Regiochemistry
11.2K
Elimination reactions of alkyl halides can yield one or more alkenes depending on the specific regiochemical and stereochemical considerations. While the regiochemistry of the reaction governs the location of the double bond in the product, the stereochemical requirements often influence the geometry.
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major...
When a substrate with two different β hydrogens undergoes an E2 elimination, the presence of a strong base can yield two regioisomeric alkenes. The more-substituted alkene is the major...
11.2K