Abstract
Cells 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.
| Original language | American English |
|---|---|
| Article number | 103852 |
| Journal | iScience |
| Volume | 25 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 18 2022 |
ASJC Scopus subject areas
- General
Keywords
- Biophysical chemistry
- Mathematical biosciences
- Molecular dynamics