Occurrence of an unusual amount of an odd-numbered fatty acid in glycosphingolipids from human cataracts

Robert V.P. Tao, University of Illinois College of Medicine
Bee Chen Lee, University of Illinois College of Medicine
Thomas C.Y. Hsieh, University of Illinois College of Medicine
Roger A. Laine, University of Illinois College of Medicine

Abstract

Human cataractous glycosphingolipids were isolated and purified according to previously established procedures. Fatty acid analyses of the purified glycosphingolipid revealed the presence of a significant amount of an odd-chain fatty acid. This was confirmed by methane (CH4) chemical ionization mass spectrometry, which showed characteristic ions at m/z 397, 425, 437, and 365. These ions facilitated the determination of molecular weight and the assignment of C25.0 (n-penta-cosanoic acid) to this fatty acid in question. This may be the first time that such an unusual distribution of a single odd-chain fatty acid has been shown to occur in a glycosphingolipid from any tissue. © 1987 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.