The effects of the guanosine diphosphate esters of 4-deoxy-4-fluoro-D-mannose (GDP-4FMan) and 4-deoxy-D-mannose (GDP-4dMan) on reactions of the dolichol pathway in chick-embryo cell microsomal membranes were investigated by studies with chick-embryo cell microsomal membranes in vitro and in baby-hamster kidney (BHK) cells in vivo. Each nucleotide sugar analogue inhibited lipid-linked oligosacch...

GlcNAc-1-P transferase (GPT) transfers GlcNAc-1-P from UDP-GlcNAc to dolichol-P (Dol-P), forming GlcNAc-P-PDol to initiate synthesis of the lipid-linked oligosaccharide Glc3Man9GlcNAc2-P-P-dolichol (G3M9Gn2-P-P-Dol). Elevated expression of GPT in CHO-K1 cells is known to cause accumulation of the intermediate M5Gn2-P-P-Dol, presumably by excessively consuming Dol-P and thereby hindering Dol-P-d...

Monoclonal antibodies labeled with near-infrared (NIR) fluorophores have potential use in disease detection, intraoperative imaging, and pharmacokinetic characterization of therapeutic antibodies in both the preclinical and clinical setting. Recent work has shown conjugation of NIR fluorophores to antibodies can potentially alter antibody disposition at a sufficiently high degree of labeling (D...

Dolichyl [beta-32P]pyrophosphate ([beta-32P]Dol-P-P) has been prepared chemically to study Dol-P-P phosphatase in calf brain. Calf brain microsomes catalyze the enzymatic release of 32Pi from exogenous [beta-32P]Dol-P-P by a bacitracin-sensitive reaction. [32P]Pyrophosphate was not detected with the water-soluble product even when 1 mM sodium pyrophosphate was added to impede pyrophosphatase ac...

Dolichols (Dol) are polyprenol lipids that are essential structural components of eukaryotic membranes. In addition, the phosphorylated derivatives of Dol function as lipid anchors of mono- and oligosaccharide precursors involved in protein glycosylation. The biological importance of Dol phosphates (Dol-P) is illustrated by the severe outcome of human disorders linked to Dol biosynthetic defect...