Glucosylsterol and acylglucosylsterol of snake epidermis: structure determination.

The structures of two classes of glycolipids, acylglucosylsterol and glucosylsterol, from snake epidermis have been determined by chemical, spectroscopic, and gas-liquid chromatographic methods. The acylglucosylsterol consists of a glucose molecule attached to cholesterol and an ester-linked fatty acid on carbon 6 of the sugar. The major ester-linked fatty acids are palmitic, stearic, and oleic. The glucosylsterol consists of glucose attached to cholesterol. These unusual glycolipids may play a role in epidermal barrier function in snakes and it is concluded that these sterol glycosides may remain in the reptiles as a vestige of a more primitive barrier-forming mechanism.