Composition based strategies for controlling radii in lipid nanotubes

PLoS One. 2014 Jan 2;9(1):e81293. doi: 10.1371/journal.pone.0081293. eCollection 2014.

Abstract

Nature routinely carries out small-scale chemistry within lipid bound cells and organelles. Liposome-lipid nanotube networks are being developed by many researchers in attempt to imitate these membrane enclosed environments, with the goal to perform small-scale chemical studies. These systems are well characterized in terms of the diameter of the giant unilamellar vesicles they are constructed from and the length of the nanotubes connecting them. Here we evaluate two methods based on intrinsic curvature for adjusting the diameter of the nanotube, an aspect of the network that has not previously been controllable. This was done by altering the lipid composition of the network membrane with two different approaches. In the first, the composition of the membrane was altered via lipid incubation of exogenous lipids; either with the addition of the low intrinsic curvature lipid soy phosphatidylcholine (soy-PC) or the high intrinsic curvature lipid soy phosphatidylethanolamine (soy-PE). In the second approach, exogenous lipids were added to the total lipid composition during liposome formation. Here we show that for both lipid augmentation methods, we observed a decrease in nanotube diameter following soy-PE additions but no significant change in size following the addition of soy-PC. Our results demonstrate that the effect of soy-PE on nanotube diameter is independent of the method of addition and suggests that high curvature soy-PE molecules facilitate tube membrane curvature.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Glycine max / chemistry
  • Lipids / chemistry*
  • Liposomes / chemistry
  • Nanotubes / chemistry*
  • Phosphatidylcholines / chemistry
  • Phosphatidylethanolamines / chemistry

Substances

  • Lipids
  • Liposomes
  • Phosphatidylcholines
  • Phosphatidylethanolamines
  • phosphatidylethanolamine

Grants and funding

This work has been funded by The Swedish Research Council with grant ID 80348401, 80348402, and 349-2007-8680. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.