Disease relevance of BF4249

• It could be converted to a sharper band (apparent Mr 23000) by treatment with endo-beta-galactosidase from Bacteroides fragilis and so probably contains one or more sites at which an oligosaccharide of the poly(N-acetyl-lactosamine) type is attached [1].

High impact information on BF4249

• A considerable portion of neutral alditols is represented by branched isomers of the linear species, which are distinguished by their content of 3,6-disubstituted galactose and their partial resistance to endo-beta-galactosidase digestion [2].
• (iii) At an optimal concentration of detergent, the endo-beta-galactosidase susceptibility of the GlcNAc beta 1-3Gal beta 1-4Glc sequence near the ceramide moiety of branched glycolipids is similar to that of the corresponding sequence in linear glycolipids [3].
• Endo-beta-galactosidase from Bacteroides fragilis cleaved 2 at one site only, yielding the disaccharide GlcNAc beta 1-3Gal (4) and the branched tetrasaccharide GlcNAc beta 1-3(GlcNAc beta 1-6)Gal beta 1-4GlcNAc (5) [4].
• 500 MHz 1H n.m.r. of oligosaccharides of N-acetyl-lactosamine-type released from human erythrocyte glycopeptides by endo-beta-galactosidase [5].
• Cleavage of the intact, endo-beta-galactosidase-treated, photoaffinity-labelled protein at its cysteine residues with 2-nitro-5-thiocyanobenzoic acid yielded a prominent, unlabelled fragment of apparent Mr 38000 and several smaller fragments which stained less intensely on SDS/polyacrylamide gels [1].

Chemical compound and disease context of BF4249

• Six strains of Bacteroides fragilis were examined and all found to produce endo-beta-galactosidase, an enzyme that hydrolyses internal beta-galactosidic linkages of oligosaccharides belonging to the poly-N-acetyl-lactosamine series, with the common structure GlcNAc beta 1 leads to 3Gal beta 1 leads to 4GlcNAc/Glc [6].
• Tetraantennary oligosaccharides with N-acetyllactosamine repeats could be digested quantitatively with endo-beta-galactosidase from Bacteroides fragilis, whereas under the same conditions tri' antennary oligosaccharides hardly reacted (< 15%) [7].
• Characterisation of oligosaccharides released from human-blood-group O erythrocyte glycopeptides by the endo-beta-galactosidase of Bacteroides fragilis. A study of the enzyme susceptibility of branched poly(N-acetyllactosamine) structures [8].
• Endo-beta-galactosidase (Bacteroides fragilis) liberated from the deacetylated material two glycosphingolipids, which were identified by fast atom bombardment-mass spectrometry as Hex-Cer and HexNAc-Hex-Hex-Cer with sphingosine and mainly 24 and 22 carbon fatty acids [9].

Anatomical context of BF4249

• Embryos cultured in the presence of endo-beta-galactosidase from the 2- to 4-cell stage onwards, or treated with the enzyme at the compacting 8-cell stage, continued to compact and proceeded to form blastocysts at the normal rate [10].

Associations of BF4249 with chemical compounds

• Kinetic studies on endo-beta-galactosidase by a novel colorimetric assay and synthesis of N-acetyllactosamine-repeating oligosaccharide beta-glycosides using its transglycosylation activity [11].
• Novel chromogenic substrates for endo-beta-galactosidase were designed on the basis of the structural features of keratan sulfate [11].
• A colorimetric assay for endo-beta-galactosidase was developed using the synthetic substrates on the basis of the determination of p-nitrophenol liberated from GlcNAcbeta-pNP or Glcbeta-pNP formed by the enzyme through a coupled reaction involving beta-N-acetylhexosaminidase (beta-NAHase) or beta-d-glucosidase [11].
• On the assumption that recompaction and de novo compaction occur by similar mechanisms, we propose that carbohydrate-binding molecules are involved which have high affinities for poly-N-acetyllactosamine structures and protect them from digestion by endo-beta-galactosidase [10].

Analytical, diagnostic and therapeutic context of BF4249

• Structural information on the major oligosaccharides was obtained from (a) their susceptibilities to endo-beta-galactosidase before and after desulphation, (b) their elution positions on a column of Bio-Gel P-4 and retention times on a high-performance anion-exchange column and (c) negative-ion fast-atom-bombardment mass spectrometry [12].
• After treatment with the culture supernatant of Bacteroides fragilis or with an endo-beta-galactosidase from Escherichia freundii, the human red blood cells are Tk-activated, i.e. agglutinable by BS II lectin and their blood group I and i activities are reduced [13].

References