Glucosylceramides of pig epidermis: structure determination.

Six series of glucosylceramides from pig epidermis have been identified, and their structures have been determined. The structural types identified are: 1, N-acylglucosylsphingosines (33%); 2, N-acylglucosylphytosphingosines (13%); 3, N-(omega-hydroxyacyl)-glucosylsphingosines (3%); 4, N-(alpha-hydroxyacyl)-glucosylphingosines (15%); 5, N-(alpha-hydroxyacyl)-glucosylsphingosines (16%); 6, N-(alpha-hydroxyacyl)-glucosylphytosphingosines (20%). The 4th and 5th classes of glucosylceramides differ in that the former contains mostly 24- to 28-carbon alpha-hydroxyacids, while the latter contains mostly alpha-hydroxypalmitic acid.