{"title":"Characterizing the heterogeneity of membrane liquid-ordered domains","authors":"Tanmoy Sarkar, Oded Farago","doi":"10.1140/epje/s10189-023-00359-7","DOIUrl":null,"url":null,"abstract":"<div><p>We use a lattice model of a ternary mixture containing saturated and unsaturated lipids with cholesterol (Chol), to study the structural properties characterizing the coexistence between the liquid-disordered and liquid-ordered phases. Depending on the affinity of the saturated and unsaturated lipids, the system may exhibit macroscopic (thermodynamic) liquid–liquid phase separation or be divided into small-size liquid-ordered domains surrounded by a liquid-disordered matrix. In both cases, it is found that the nanoscale structure of the liquid-ordered regions is heterogeneous, and that they are partitioned into Chol-rich sub-domains and Chol-free, gel-like, nano-clusters. This emerges as a characteristic feature of the liquid-ordered state, which helps distinguishing between liquid-ordered domains in a two-phase mixture, and similar-looking domains in a one-phase mixture that are rich in saturated lipids and Chol, but are merely thermal density fluctuations. The nano-structure heterogeneity of the liquid-ordered phase can be detected by suitable experimental spectroscopic methods and is observed also in atomistic computer simulations.</p></div>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"46 10","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"The European Physical Journal E","FirstCategoryId":"4","ListUrlMain":"https://link.springer.com/article/10.1140/epje/s10189-023-00359-7","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
We use a lattice model of a ternary mixture containing saturated and unsaturated lipids with cholesterol (Chol), to study the structural properties characterizing the coexistence between the liquid-disordered and liquid-ordered phases. Depending on the affinity of the saturated and unsaturated lipids, the system may exhibit macroscopic (thermodynamic) liquid–liquid phase separation or be divided into small-size liquid-ordered domains surrounded by a liquid-disordered matrix. In both cases, it is found that the nanoscale structure of the liquid-ordered regions is heterogeneous, and that they are partitioned into Chol-rich sub-domains and Chol-free, gel-like, nano-clusters. This emerges as a characteristic feature of the liquid-ordered state, which helps distinguishing between liquid-ordered domains in a two-phase mixture, and similar-looking domains in a one-phase mixture that are rich in saturated lipids and Chol, but are merely thermal density fluctuations. The nano-structure heterogeneity of the liquid-ordered phase can be detected by suitable experimental spectroscopic methods and is observed also in atomistic computer simulations.
期刊介绍:
EPJ E publishes papers describing advances in the understanding of physical aspects of Soft, Liquid and Living Systems.
Soft matter is a generic term for a large group of condensed, often heterogeneous systems -- often also called complex fluids -- that display a large response to weak external perturbations and that possess properties governed by slow internal dynamics.
Flowing matter refers to all systems that can actually flow, from simple to multiphase liquids, from foams to granular matter.
Living matter concerns the new physics that emerges from novel insights into the properties and behaviours of living systems. Furthermore, it aims at developing new concepts and quantitative approaches for the study of biological phenomena. Approaches from soft matter physics and statistical physics play a key role in this research.
The journal includes reports of experimental, computational and theoretical studies and appeals to the broad interdisciplinary communities including physics, chemistry, biology, mathematics and materials science.