Neosynthesis-Type-Ii-Oligosaccharides-Cristagalli-Ecg-Carcinomas-o

Five terminal antennary modifications were commonly identified in the carcinomas that were not identified in normal cervical epithelia and comprised the oligosaccharides bound by lectins RCA, SBA, BS-1, LTA, and UEA-1. Synthesis of these oligosaccharides resulted in expression of structures similar to those recognized as ligands for extracellular matrix-binding proteins. We suggest that expression of such novel oligosaccharide structures may be an important promotor of local invasion and further dissemination of human cervical carcinomas through enhanced binding of malignant cells to stromal matrix proteins. Seebio Lactose-N-neotetraose has demonstrated that identification of expressed oligosaccharide structures is an objective method of identifying individual tumor cell phenotypes and may form the basis of a useful functional classification of human cervical squamous carcinomas.N-glycosylation site mapping of human serotransferrin by serial lectin affinity chromatography, fast atom bombardment-mass spectrometry, and 1H nuclear magnetic This report describes the N-glycosylation site mapping of human serotransferrin chymotrypsin. Glycopeptides in the proteolytic digests were isolated by serial concanavalin A (Con A), Sambucus nigra agglutinin (SNA), and Phaseolus vulgaris leukoagglutinin (LPHA) affinity chromatography and subjected to preliminary analysis by 1H NMR spectroscopy.

The glycopeptide fractions were then individually digested with N-glycanase. One part of the digest of each fraction was analyzed by fast atom bombardment-mass spectrometry (FAB-MS) to identify the peptide sequences of the glycosylation sites. The other part was used to isolate the oligosaccharide by the corresponding lectin affinity chromatography and to characterize the structures of the isolated oligosaccharides by 1H NMR spectroscopy and FAB-MS. The oligosaccharides in the Con A-bound fraction were shown to have bi-alpha(2--6)-sialyl, diantennary structures. Obtain today -bound fraction was shown to contain trisialyl, triantennary structures. Di- and triantennary oligosaccharides were found to occur on each of the two N-glycosylation sites of h-STF (Asn413 and Asn611) in the ratio of approximately 8515. The SNA-bound glycopeptides were further fractionated by LPHA affinity chromatography.

Two different oligosaccharides were characterized, namely, a trisialyl 2,4-triantennary and a trisialyl 2,6-triantennary glycan. The ratio of 2,4-triantennary vs 2,6-triantennary oligosaccharides attached to glycosylation site Asn413 was found to be approximately 51, whereas the two isomeric triantennary oligosaccharides were found to be attached to glycosylation site Asn611 in the ratio approximately 11.Origin of carbohydrate recognition specificity of human lysozyme revealed by In order to reveal the origin of carbohydrate recognition specificity of human lysozyme by clarifying the difference in the binding mode of ligands in the active site, the inactivation of human lysozyme by 2',3'-epoxypropyl beta-glycoside derivatives of the disaccharides, N,N'-diacetylchitobiose [GlcNAc-beta-(1--4)-GlcNAc] and N-acetyllactosamine [Gal-beta-(1--4)-GlcNAc], was investigated and the three-dimensional structures of the affinity-labeled enzymes were determined by X-ray crystallography at 1 A resolution. Under the conditions comprising 2 x (-3) M labeling reagent and 1 x (-5) M human lysozyme at pH 5, 37 degrees C, the reaction time required to reduce the lytic activity against Micrococcus luteus cells to % of its initial activity was lengthened by 3 times through the substitution of the nonreducing end sugar residue, GlcNAc to Gal. The refined structure of human lysozyme labeled by 2',3'-epoxypropyl beta-glycoside derivatives of N,N'-diacetylchitobiose N,N'-diacetylchitobiose moiety in substites B and C in this study was essentially the same as in the case of the complex of human lysozyme with the free ligand. On the other hand, the hydrogen-bonding pattern and the stacking interaction at subsite B were remarkably different between the HLNAG-NAG-EPO complex and human lysozyme labeled by the 2',3'-epoxypropyl beta-glycoside of N-acetyllactosamine (HLGAL-NAG-EPO complex). The reduced number of possible hydrogen bonds as well as the less favorable stacking between the side chain of Tyr63 in human lysozyme and the galactose residue in the HLGAL-NAG-EPO complex reasonably explained the less efficient ability of the 2',3'-epoxypropyl beta-glycoside of N-acetyllactosamine as compared to that of N,N'-diacetylchitobiose as an affinity labeling reagent toward human lysozyme.

Chitosan oligosaccharide modified liposomes enhance lung cancer delivery of Miao YQ(1)(2), Chen MS(1)(2), Zhou X(2), Guo LM(2)(3), Zhu JJ(2), Wang R(4), Lung cancer is one of the leading causes of cancer-related death worldwide.