Biosynthesis of glycoconjugates in mitochondrial outer membranes. Preliminary characterization of the oligosaccharide moiety of a N-glycoprotein.
Outer mitochondrial membranes synthesize a N-glycoprotein by a direct incorporation of sugars from their nucleotide-donors into an endogenous protein acceptor. To characterize the oligosaccharide moiety of this N-glycoprotein, we sequentially incorporated [14C]-sugars into the protein acceptor. After pronase digest, the released [14C]-glycopeptides were fractionated on a QAE-Sephadex column which gave rise to 9% of neutral glycopeptides and 91% of charged glycopeptides. These latter were identified as bearing phosphate residues in the form of monoester (28%) and acid-stable diester (63%). The oligosaccharide moiety of this mitochondrial glycoprotein has been characterized as incomplete biantennary complex-type chains.
Levrat
C
C
Department of General and Medical Biochemistry, INSERM U 189, Lyon-Sud Medical School, University of Lyon, Oullins, France.
Ardail
D
D
Louisot
P
P
D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D006020:Glycopeptides / Q000032:analysis; D006023:Glycoproteins / Q000032:analysis / Q000096:biosynthesis*; D006031:Glycosylation; D007425:Intracellular Membranes / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism* / Q000648:ultrastructure; D009844:Oligosaccharides / Q000032:analysis; D010710:Phosphates / Q000378:metabolism; D011402:Pronase / Q000378:metabolism
D006020:Glycopeptides; D006023:Glycoproteins; D009844:Oligosaccharides; D010710:Phosphates; D011402:Pronase