文章基本信息

标题：Surface tension and super-stoichiometric surface enrichment in two-component biomolecular condensates
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作者：Andrew G.T. Pyo ; Yaojun Zhang ; Ned S. Wingreen 等
期刊名称：iScience
印刷版ISSN：2589-0042
出版年度：2022
卷号：25
期号：2
页码：1-12
DOI：10.1016/j.isci.2022.103852
语种：English
出版社：Elsevier
摘要：SummaryCells can achieve internal organization by exploiting liquid-liquid phase separation to form biomolecular condensates. Here we focus on the surface properties of condensates composed of two multivalent associative polymers held together by one-to-one “sticker” bonds. Using coarse-grained molecular-dynamics simulations, we study the influence of component stoichiometry on condensate surface properties. We find that unequal stoichiometry results in enrichment of the majority species at the interface and a sharp reduction of surface tension. To relate these two effects, we show that the reduction in surface tension scales linearly with the excess concentration of free binding sites at the interface. Our results imply that each excess free site contributes an approximately fixed additional energy and entropy to the interface, with the latter dominating such that enrichment of free majority sites lowers the surface tension. Our work provides insight into novel physical mechanisms by which cells can regulate condensate surface properties.Graphical abstractDisplay OmittedHighlights•Stoichiometry controls the surface tension of two-component biomolecular condensates•Unequal stoichiometry leads to enrichment of the majority species at the interface•Enrichment of the free majority binding sites increases the interfacial entropy•Surface tension is drastically reduced at unequal stoichiometryBiophysical chemistry; Molecular dynamics; Mathematical biosciences