Affordable Access

Publisher Website

Chiral discrimination inN-tetradecanoylalanine andN-tetradecanoylalanine/ditetradecanoylphosphatidylcholine monolayers

Authors
Journal
Biochimica et Biophysica Acta (BBA) - Biomembranes
0005-2736
Publisher
Elsevier
Publication Date
Volume
938
Issue
3
Identifiers
DOI: 10.1016/0005-2736(88)90137-x
Keywords
  • Phosphatidylcholine Monolayer
  • Chiral Property
  • Myristoylalanine

Abstract

Abstract Surface pressure-area per molecule isotherms have been obtained for N- tetradecanoly- l-alanine (myristoyl- l-alanine, l-MA), N- myristoyl- d-alanine ( d-MA) and their mixtures at the air/water interface at various temperatures to detect an eventual chiral discrimination occurring in N-acylamino-acid monolayers. It was found that the racemic mixture d-MA + l-MA exhibits, at a given temperature, a more expanded state than that of the pure enantiomeric one. Besides, the phase diagram of l-MA/ d-MA binary mixtures gives a positive azeotropy which means that the interactions between the two enantiomeric molecules ( l- d) are weaker than the interactions between the pure chiral molecules ( l- l or d- d), these interactions being at their minimum level when the mixture corresponds to the racemic composition. Any measurable difference in the interactions between two different chiral molecules is referred to as a diastereoisomer discrimination, compared to an enantiomer discrimination between two antipodes. This was checked through l-dimyristoylphosphatidylcholine l-DMPC)/ l- and d-MA mixed monolayer studies. No difference was observed in the phase diagram of binary mixtures of l-DMPC/ l-MA and l-DMPC/ d-MA, which shows that, in such systems, diastereoisomer interactions cannot occur because of the relative inaccessibility of the phospholipid chiral center.

There are no comments yet on this publication. Be the first to share your thoughts.