title: Experimental support for tilt-dependent theory of biomembrane mechanics.
abstract: Recent simulations have indicated that the traditional model for topographical fluctuations in biomembranes should be enriched to include molecular tilt. Here we report the first experimental data supporting this enrichment. Utilizing a previously posited tilt-dependent model, a height-height correlation function was derived. The x-ray scattering from a liquid crystalline stack of oriented fluid phase lipid bilayers was calculated and compared with experiment. By fitting the measured scattering intensity, both the bending modulus K(c)=8.3±0.6×10⁻²⁰ J and the tilt modulus K(θ)=95±7  mN/m were determined for DOPC lipid bilayers at 30 °C.
authors.affiliation: Physics Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Jablin
authors.affiliation: Physics Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: K
authors.initials: K
authors.lastname: Akabori
authors.affiliation: Physics Department, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Nagle
mesh_terms: D001696:Biomechanical Phenomena; D003198:Computer Simulation; D008051:Lipid Bilayers / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry; D008566:Membranes / Q000737:chemistry* / Q000502:physiology*; D008954:Models, Biological; D010713:Phosphatidylcholines / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D008051:Lipid Bilayers; D010713:Phosphatidylcholines; C017251:1,2-oleoylphosphatidylcholine