Self-Emergent Protocells Generated in an Aqueous Solution with Binary Macromolecules through Liquid-Liquid Phase Separation

Chembiochem. 2020 Dec 1;21(23):3323-3328. doi: 10.1002/cbic.202000344. Epub 2020 Aug 11.

Abstract

Recently, liquid-liquid phase separation (LLPS) has attracted considerable attention among researchers in the life sciences as a plausible mechanism for the generation of microstructures inside cells. LLPS occurs through multiple nonspecific interactions and does not always require a lock-and-key interaction with a binary macromolecular solution. The remarkable features of LLPS include the non-uniform localization and concentration of solutes, resulting in the ability to isolate certain chemical systems and thereby parallelize multiple chemical reactions within the limited space of a living cell. We report that, by using the macromolecules, poly(ethylene glycol) (PEG) and dextran, that exhibit LLPS in an aqueous solution, cell-sized liposomes are spontaneously formed therein in the presence of phospholipids. In this system, LLPS is generated through the depletion effect of macromolecules. The results showed that cell-like microdroplets entrapping DNA wrapped by a phospholipid layer emerge in a self-organized manner.

Keywords: DNA; liquid-liquid phase separation; membraneless cell organelles; microdroplets; synthetic biology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA / chemistry
  • Dextrans / chemistry*
  • Lipid Droplets / chemistry*
  • Macromolecular Substances / chemistry
  • Particle Size
  • Phospholipids / chemistry
  • Polyethylene Glycols / chemistry*
  • Solutions
  • Water / chemistry

Substances

  • Dextrans
  • Macromolecular Substances
  • Phospholipids
  • Solutions
  • Water
  • Polyethylene Glycols
  • DNA