Self-reproducing catalyst drives repeated phospholipid synthesis and membrane growth

Proc Natl Acad Sci U S A. 2015 Jul 7;112(27):8187-92. doi: 10.1073/pnas.1506704112. Epub 2015 Jun 22.

Abstract

Cell membranes are dynamic structures found in all living organisms. There have been numerous constructs that model phospholipid membranes. However, unlike natural membranes, these biomimetic systems cannot sustain growth owing to an inability to replenish phospholipid-synthesizing catalysts. Here we report on the design and synthesis of artificial membranes embedded with synthetic, self-reproducing catalysts capable of perpetuating phospholipid bilayer formation. Replacing the complex biochemical pathways used in nature with an autocatalyst that also drives lipid synthesis leads to the continual formation of triazole phospholipids and membrane-bound oligotriazole catalysts from simpler starting materials. In addition to continual phospholipid synthesis and vesicle growth, the synthetic membranes are capable of remodeling their physical composition in response to changes in the environment by preferentially incorporating specific precursors. These results demonstrate that complex membranes capable of indefinite self-synthesis can emerge when supplied with simpler chemical building blocks.

Keywords: autocatalysis; lipids; membranes; self-assembly.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Catalysis
  • Cell Membrane / chemistry*
  • Cell Membrane / metabolism
  • Copper / chemistry
  • Copper / metabolism
  • Cycloaddition Reaction
  • Lipid Bilayers / chemistry*
  • Lipid Bilayers / metabolism
  • Magnetic Resonance Spectroscopy
  • Membrane Lipids / chemical synthesis
  • Membrane Lipids / chemistry*
  • Membrane Lipids / metabolism
  • Membranes, Artificial*
  • Microscopy, Confocal
  • Microscopy, Electron, Transmission
  • Models, Chemical
  • Molecular Structure
  • Phosphatidylcholines / chemical synthesis
  • Phosphatidylcholines / chemistry
  • Phosphatidylcholines / metabolism
  • Phospholipids / biosynthesis
  • Phospholipids / chemical synthesis
  • Phospholipids / chemistry*
  • Time-Lapse Imaging
  • Triazoles / chemical synthesis
  • Triazoles / chemistry
  • Triazoles / metabolism
  • Unilamellar Liposomes / chemistry

Substances

  • Lipid Bilayers
  • Membrane Lipids
  • Membranes, Artificial
  • Phosphatidylcholines
  • Phospholipids
  • Triazoles
  • Unilamellar Liposomes
  • Copper
  • 1-palmitoyl-2-oleoylphosphatidylcholine