Molecular arrangements of sphingolipids. The monolayer behaviour of ceramides

✍ Scribed by H. Löfgren; I. Pascher

• Book ID: 103041996
• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 737 KB
• Volume: 20
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(77)90068-8

✦ Synopsis

A series of synthetic ceramides have been studied at the air-water interface b~: recording the surface pressure-area isotherms at continuous compression.

Ceramides that contain a 4,5-trans-double bond in the long chain base were found to condense into a close-packed arrangement with vertical chains already at a very low surface pressure. The oorresponding saturated compounds adopt a similar close packed arrangemen'~ only at high surface pressure. At 30 dynes/cm, a lateral pressure representative of biologlcal membranes, the area per molecule and compressibility was further found to depend on the number and configuration of the hydroxyl groups. The presence of a 2-D-hydroxyl group in the fatty acid generally promotes the condensation. A sinlilar effect is observed if the long chain base contains a 4-D-hydroxyl group. Cis-double bonds or methyl branches in the fatty acid chain, which increase the space requirement, limi: the lateral interaction of the polar group. However the 15-c/s-double bond of nervonic acid can be accommodated wi~out any distortion of the close-pacl~ing arrangement.