title: The impact of Texas red on lipid bilayer properties.
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.
authors.affiliation: Department of Chemical Engineering and Materials Science, University of California-Davis, Davis, California 95616, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Skaug
authors.forename: Marjorie L
authors.initials: ML
authors.lastname: Longo
authors.forename: Roland
authors.initials: R
authors.lastname: Faller
mesh_terms: D005456:Fluorescent Dyes / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D044366:Transition Temperature; D014966:Xanthenes / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D008055:Lipids; D014966:Xanthenes; C034657:Texas red