Core oligosaccharides

In a very elegant study, Droge and coworkers26 investigated the structures of the LPS from four Salmonella minnesota R-mutants designated mR595, mR3, mR7, and mR5. These mutants synthesize LPS that contains only lipid A and the inner core oligosaccharides,... 

Fig. 8.—Composition of the Core Oligosaccharide from a Galactose-epimeraseless mutant38 of Salmonella typhimurium,S7...

FIGURE 7-32 Bacterial lipopolysaccharides. (a) Schematic diagram of the lipopolysaccharide of the outer membrane of Salmonella ty-phimurium. Kdo is 3-deoxy-o-manno-octulosonic acid, previously called ketodeoxyoctonic acid Hep is L-glycero-D-mannoheptose AbeOAc is abequose (a 3,6-dideoxyhexose) acetylated on one of its hydroxyls. There are six fatty acids in the lipid A portion of the molecule. Different bacterial species have subtly different lipopolysaccharide structures, but they have in common a lipid region (lipid A), a core oligosaccharide, and an "O-specific" chain, which is the prin-... 

Many differences are also found in the "core" oligosaccharide (Fig. 8-30) and in the O-antigens.594 -596... 

Scheme 3.—Biosynthesis of the Core Oligosaccharide AT-Glycosylically Linked to L-Asparagine in Yeast Mannans.10 11 86 11 111-117-1 8-160-161...

The transfer of the oligosaccharide to protein is followed in vivo by the excision of the D-glucosyl residues the nine D-mannosyl residues present in the transferred oligosaccharide probably remain in the inner core of the D-mannan. However, the possibility that some D-mannosyl residues could be almost simultaneously removed and added cannot be precluded.117,167 Finally, terminal, < -d-(1 - 3)-linked D-mannosyl groups are added to the trimmed, protein-bound oligosaccharide.118 The outer chain of the d-mannan is formed after the inner-core oligosaccharide has been transferred to protein and processed, apparently by direct transfer of D-mannosyl groups from GDP-D-mannose.168 The similarity of the structures of the outer chain... 

The Core. Core oligosaccharides are structurally less diverse than O-chains. The core oligosaccharide shown in Figure 1 is common to many or all Salmonella serotypes. Distinct core types have been... 

The structures of the core oligosaccharides have not been worked out in detail, but the analytical compositions (Table 111)... 

Table III. Analytical Data for the Core Oligosaccharide of Pseudomonas aeruginosa (Relative Percentages)...

Cohen, R. E., Zhnag, W., and Ballou, C. E. (1982). Effects of mannoproteins in Saccharomyces cerevisiae core oligosaccharide structure. J. Biol. Chem., 257, 5730-5737. 

---