Transfer of Sugars from Nucleoside Diphosphosugar Compounds to Endogenous and Synthetic Dolichyl Phosphate in Human Lymphocytes

Whole cell homogenate or membranes from human lymphocytes catalyzed the transfer of sugars from nucleoside diphosphosugar compounds to lipid and complex glycan. Transfer from GDP-mannose, UDP-glucose, or UDP-acetylglucosamine to lipid was stimulated by synthetic dolichyl phosphate (a new synthesis of which is described). No lipid was produced from GDP-fucose, UDP-galactose, or CMP-sialic acid, but complex glycan was labeled in all cases. The lipid formed from GDP-mannose and either endogenous acceptor or synthetic dolichyl phosphate chromatographed in the same position as synthetic dolichyl phosphomannose in three solvent systems, and was further characterized as dolichyl phosphomannose. Products formed by stimulation with C55-ficaprenyl phosphate, C45-solanesyl phosphate, or C15-farnesyl phosphate could be distinguished chromatographically from dolichyl phosphomannose. Three lipid products were formed from UDP-glucose. The formation of one of these which chromatographed near dolichyl phosphomannose was stimulated by dolichyl phosphate. Three lipid products were formed in small amounts from UDP-acetylglucosamine. Formation of all three was stimulated by dolichyl phosphate.