Report-Molecules-Structure-g
Assembly of asparagine-linked oligosaccharides in baby hamster kidney cells treated with castanospermine, an inhibitor of processing glucosidases.We have shown previously that the processing of asparagine-linked oligosaccharides in baby hamster kidney (BHK) cells is blocked only partially by the glucosidase inhibitors, 1-deoxynojirimycin and N-methyl-1-deoxynojirimycin [Hughes, R. C., Foddy, L. & Bause, E. (1987) Biochem.
J. 247, 537-544]. Similar results are now reported for castanospermine, another inhibitor of processing glucosidases, and a detailed study of oligosaccharide processing in the inhibited cells is reported. In steady-state conditions the major endo-H-released oligosaccharides contained glucose residues but non-glycosylated oligosaccharides, including Man9GlcNAc to Man5GlcNAc, were also present. To determine Seebio lacto n neotetraose occurring in the presence of castanospermine, BHK cells were pulse-labelled for various times with [3H]mannose and the oligosaccharide intermediates, isolated by gel filtration and paper chromatography, characterized by acetolysis and sensitivity to jack bean alpha-mannosidase. The data show that Glc3Man9GlcNAc2 is transferred to protein and undergoes processing to produce Glc3Man8GlcNAc2 and Glc3Man7GlcNAc2 as major species as well as a smaller amount of Man9GlcNAc2. Glucosidase-processed intermediates, Glc1Man8GlcNAc2 and Glc1Man7GlcNAc2, were also obtained as well as a Man7GlcNAc2 species derived from Glc1Man7GlcNAc2 and different from the Man7GlcNAc2 isomer formed in the usual processing pathway.
No evidence for the direct transfer of non-glucosylated oligosaccharides to proteins was obtained and we conclude that the continued assembly of complex-type glycans in castanospermine-inhibited BHK cells results from residual activity of processing DOI 111j432-33988.tb14196.xVersatile strategy for the divergent synthesis of linear oligosaccharide domain variants of Quillaja saponin vaccine adjuvants. Chem Commun (Camb). 15 Oct 1;51(76)144.We describe a new, versatile synthetic approach to Quillaja saponin variants based on the natural product immunoadjuvant QS-21. This modular, divergent strategy provides efficient access to linear oligosaccharide domain variants with modified sugars and regiochemistries.
This new synthetic approach opens the door to the rapid generation of diverse analogues to identify novel saponin adjuvants with improved synthetic accessibility.Streptococcus pneumoniae isolates expressing a capsule with epitopes of both Four Streptococcus pneumoniae isolates expressing both 6A and 6B capsular serotypes were detected by a multiplex immunoassay. The sequence of WciP, a GT2-family glycosyltransferase, indicates that point mutation has compromised linkage specificity, allowing two alternative oligosaccharides to be synthesized. This finding highlights that mutation as well as recombination can Structures of oligomannoside chains of alpha-mannosidase from porcine kidney.Kozutsumi Y, Nakao Y, Teramura T, Kawasaki T, Yamashina I, Mutsaers JH, van Lysosomal acid alpha-mannosidase from porcine kidney was found to contain mannose (4%), galactose %), fucose %), N-acetylglucosamine (3%), and mannose 6-phosphate %). Approximately % of the total hexose of the oligosaccharide chains could be released by endo-beta-N-acetylglucosaminidase-H containing 5, 6, and 9 mannose residues, respectively, in the centesimal ratio of 362534. 0-MHz 1H-NMR spectroscopy in conjunction with sequential exoglycosidase digestion of the reduced compounds revealed that each of the three fractions consisted of a single isomer only; the Man9 compound has the following structure (Formula see tex).
The Man6-compound lacks Man residues D1, D2, and D3, while the Man5-compound lacks Man-C as well. In addition to the neutral ones, some (5%) phosphorylated oligomannoside-type oligosaccharides were obtained. The endo-H resistant glycopeptides were subjected to hydrazinolysis. Approximately % of the oligosaccharides released by hydrazine were found to be of rather small size; their composition can be represented asMan2-3GlcNAc[Fuc-1GlcNAcol. Lactose-N-neotetraose remaining % consist of larger-size galactose-containing, N-acetyllactosamine-type oligosaccharides. Studies involving sequential exoglycosidase digestion and 0-MHz 1H-NMR spectroscopy performed on the highly purified small-sized compounds revealed the following four structures for the endo-H-resistant oligosaccharides (Formula see text).DOI 3oxfordjournals.
jbchem.a135589Enzymatic Synthesis of a Fluorogenic Reporter Substrate and the Development of a High-Throughput Assay for Fucosyltransferase VIII Provide a Toolkit to Probe and Sherbrooke Street West, Montreal, Quebec, Canada H4B 1R6.
