The impact of Texas red on lipid bilayer properties

J Phys Chem B. 2011 Jul 7;115(26):8500-5. doi: 10.1021/jp203738m. Epub 2011 Jun 14.

Abstract

We investigated the impact of fluorescent labeling on the properties of a lipid bilayer using atomistic molecular dynamics simulation. The system consisted of 24 Texas Red-1,2-dihexadecanoyl-sn-glycero-3-phophoethanolamine (TR-DHPE) in a bilayer of 488 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipids. We found binding between TR-DHPE and DPPC caused by electrostatic interactions. On average, TR-DHPE is bound to 1.2 DPPC molecules. Binding reduced the diffusion coefficient of TR-DHPE by 34% relative to unlabeled DPPC molecules. We estimate that binding would lead to a ∼ 5 °C increase in the liquid to liquid-ordered transition temperature of a ternary lipid system. These results emphasize the importance of considering the impact of fluorescence labeling when interpreting experimental results.

Publication types

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

MeSH terms

  • Fluorescent Dyes / chemistry*
  • Lipid Bilayers / chemistry*
  • Lipids / chemistry
  • Molecular Dynamics Simulation
  • Molecular Structure
  • Transition Temperature
  • Xanthenes / chemistry*

Substances

  • Fluorescent Dyes
  • Lipid Bilayers
  • Lipids
  • Xanthenes
  • Texas red