Molecular Theory Applied to Lipid Bilayers and Lipid–Protein Interactions

Part of the Handbook of Modern Biophysics book series (HBBT)


The fundamental, necessary components of biomembranes are the lipids that form the membrane bilayer. Although a typical plasma membrane is composed of about 50% percent proteins by mass [1], the lipids provide the structure of the membrane through their self-assembly into a bilayer. The self-assembly is driven by the amphiphilic nature of the lipids: they contain a headgroup that is hydrophilic and a tailgroup that is hydrophobic. The basic principles of lipid self-assembly are well understood [2]. The physical properties and behavior of the lipid bilayer have been studied theoretically using a variety of models and techniques. With increasing computational resources available, a popular approach has been to study membranes using atomistic molecular dynamics (MD) simulations. In such simulations, all the atoms are represented explicitly. The interactions between atoms are described by effective potentials which must be obtained through either quantum mechanical calculations or by fitting various properties to experiment. Such simulations istic MD simulations have been able to treat patches of membrane up to a few tens of nanometers in lateral extent, over timescales of a few tens of nanoseconds.


Density Functional Theory Lipid Bilayer Chem Phys Density Profile Bilayer Thickness 
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© Humana Press 2009

Authors and Affiliations

  1. 1.Sandia National LaboratoriesNew MexicoUSA
  2. 2.Colder InsightsMinnesotaUSA

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