Vesicle Shapes and Shape Transformations: A Systematic Study

  • Karin Berndl
  • Josef Käs
  • Reinhard Lipowsky
  • Erich Sackmann
  • Udo Seifert
Part of the NATO ASI Series book series (NSSB, volume 263)

Abstract

The lipid bilayer vesicle is the simplest possible model of biological membranes. Nevertheless, it exhibits already a number of typical properties of cell membranes. The most fascinating examples are the shape transitions and shape instabilities. It has been recognized long ago that shape transitions may be induced by changing the osmotic conditions or the temperature1. Apart from spherical and ellipsoidal shapes more exotic shapes such as e. g. discocytes, stomatocytes1, echinocytes2 or a necklace of small vesicles3 has recently been observed. Up to now, our understanding of these shape transformations has been rather limited. Indeed, all previous experiments have been performed with relatively complex systems containing, e. g. charged and unsaturated lipids, mixtures of different lipids or additional solutes such as sugar in the aqueous phase. It was generally believed that these different ingredients play an essential role in determining the vesicle shape. Therefore, no attempt has been reported so far to relate these experimentally observed shapes in a systematic way to theoretical calculations.

Keywords

Shape Transition Area Difference Spontaneous Curvature Cover Slide Prolate Ellipsoid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1991

Authors and Affiliations

  • Karin Berndl
    • 1
  • Josef Käs
    • 2
  • Reinhard Lipowsky
    • 1
  • Erich Sackmann
    • 2
  • Udo Seifert
    • 1
  1. 1.Sektion PhysikUniversität MünchenMünchen 2Germany
  2. 2.Physik Department, Biophysics Group (E22)Technische Universität MünchenGarchingGermany

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