title: Synthesis of beta-glucans in Prototheca zopfii. Isolation and characterization of the glycoprotein primer.
abstract: When Prototheca zopfii cells were pulse-labeled with 14C-containing amino acids and homogenized, 14C-labeled membranes were obtained. In vitro incubations with the previously labeled membranes and UDP-[3H]Glc produced a trichloroacetic-acid-insoluble fraction having both isotopes. A double-labeled glucoprotein was isolated and characterized. It has a relative molecular mass of 28,000-30,000 and a carbohydrate content of 10%. The oligosaccharide chain is linked to the protein through an O-glycosidic bond between hydroxyproline and glucose. The oligosaccharide has a polymerization degree ranging over 10-20 hexose units. Glucose is the only monosaccharide found; most of the glucose residues are beta-1,4-linked (90%) but some are beta-1,3-linked (10%).
mesh_terms: D002473:Cell Wall / Q000378:metabolism; D005591:Chemical Fractionation; D000460:Chlorophyta / Q000378:metabolism*; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005936:Glucans / Q000096:biosynthesis*; D006023:Glycoproteins / Q000302:isolation & purification*; D009844:Oligosaccharides / Q000302:isolation & purification; D010455:Peptides / Q000302:isolation & purification
chemical_list: D005936:Glucans; D006023:Glycoproteins; D009844:Oligosaccharides; D010455:Peptides