Advertisement

Biophysics of structure and mechanism

, Volume 6, Supplement 1, pp 111–111 | Cite as

Calorimetric studies on saturated mixed-chain lecithin-water systems. The nonequivalence of acyl chains in the thermotropic phase transition

  • Jürgen Stümpel
  • Alfar Nicksch
  • Hansjörg Eibl
Section: Cell and Membrane Research E: Membrane Structure anf Dynamics
  • 14 Downloads

Abstract

Calorimetric measurements were performed on various lecithin-water systems in which the lecithins, analogously to the naturally occuring ones, have different fatty acid residues in the 1 and 2 position of the glycerol backbone. The data show that variation of the acyl chains either have no influence upon, or contribute 0.5 Kcal/mol per CH2-segment to the phase transition enthalpy.

Futhermore one can conclude that the effectively shorter chain in the mixed-chain lecithins determines, regardless of its position, the magnitude of the transition enthalpy δHm.

The pre-transition behaviour is determined by the effective chain lengths and their position on the glycerol backbone. In one case (1M-2S-PC) it could be shown that there is no calorimetrically detectable pre-transition. Thus, in order to understand the phase transition behaviour of phospholipid-water systems it is not enough to know only the number of CH2-segments but also equally important are the effective chain lengths and the positions on the glycerol backbone.

Keywords

Glycerol Enthalpy Phase Transition Plant Physiology Lecithin 
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.

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • Jürgen Stümpel
    • 1
  • Alfar Nicksch
    • 1
    • 2
  • Hansjörg Eibl
    • 1
  1. 1.Max-Planck-Institut für biophysikalische ChemieGöttingenF.R.G.
  2. 2.Institut für Biochemie der Freien Universität BerlinBerlin 33F.R.G.

Personalised recommendations