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1.
The TF, Tn, and SiaTn glycotopes are frequently expressed in cancer-associated mucins. Antibodies to these glycotopes were found in human serum. A set of polyacrylamide (PAA)--based glycoconjugates was applied to the direct and competitive enzyme-linked immunosorbent assays (ELISA) to characterize the specificity of serum IgG antibodies. The anti-TF, -Tn and -SiaTn IgG were affinity purified from serum of cancer patients and characterized using PAA-conjugates and free saccharides. The anti-TF and -Tn antibodies were shown to be specific. The anti-TF IgG bound both Galbeta1-3GalNAcalpha- and Galbeta1-3GalNAcbeta-PAA, the latter was three-four times more effective inhibitor of antibody binding. The anti-Tn IgG reacted only with GalNAcalpha-PAA. The anti-SiaTn IgG cross-reacted with Tn-PAA but SiaTn-PAA was five-six times more effective inhibitor in a competitive assay. The IC50 values for PAA-conjugates with the corresponding antibodies typically ranged from 2 to 5 x 10(-8) M. The antibodies display a low specificity to mucin-type glycoconjugates in comparison with PAA-conjugates as was shown for mucins isolated from human malignant tumor tissues, ovine submaxillary mucin (OSM) and asialo-OSM. The unusual IgG-antibody specificity to GalNAcbeta and GalNAcbeta1-3GalNAcbeta ligands was found in human serum. 相似文献
2.
Rare polyagglutinable NOR erythrocytes contain unusual globoside extention products terminating with a Galα1-4GalNAcβ1-3Gal-
unit. This trisaccharide epitope is recognized by recently characterized antibodies naturally occurring in most human sera
(Duk et al., Glycobiology, 15, 109, 2005). These antibodies represent two major types of fine specificity. All these antibodies are most strongly inhibited by Galα1-4GalNAcβ1-3Gal
(NOR-tri), and weakly by Galα1-4Gal. However, the type 1 antibodies are strongly inhibited by Galα1-4Galβ1-3Gal-R and weakly
by Galα1-4GalNAc, while the type 2 antibodies show the opposite reactivities with these two oligosaccharides. Similar antibodies
have now been found in horse, rabbit and pig sera. The antibodies were purified from animal sera by affinity chromatography
on Galα1-4GalNAcβ1-3Gal-human serum albumin(HSA)-Sepharose 4B conjugate. The specificity of the antibodies was determined
by binding to ELISA plates coated with several α-galactosylated oligosaccharide-polyacrylamide (PAA) or -HSA conjugates and
by inhibition with synthetic oligosaccharides. The purified antibodies bound specifically to conjugates containing NOR-tri.
The inhibition of binding showed that the animal sera also contain two types of anti-NOR antibodies: type 2 was found in the
horse serum, and a mixture of both types was present in rabbit and pig serum. These results indicate that anti-NOR, a new
and distinct kind of anti-αGal antibody, are present in animal sera and show similar specificties and diversity as their counterparts
found in human sera. 相似文献
3.
Daisei Miyamoto Takao Ueno Sachiko Takashima Kazuhide Ohta Toshio Miyawaki Takashi Suzuki Yasuo Suzuki 《Glycoconjugate journal》1997,14(3):379-388
A new monoclonal antibody (TU-1) directed against the Galα1-4Galβ1-4Glc residue of the Gb3Cer/CD77 antigen was prepared by
the hybridoma technique following immunization of mice with an emulsion composed of monophosphoryl lipid A, trehalose dimycolate,
and Gb3Cer isolated from porcine erythrocytes. TU-1 showed reactivity towards Gb3Cer and lyso-Gb3Cer (Galα1-4Galβ1-4Glcβ1-1′Sph),
although the reactivity towards lyso-Gb3Cer was about 10-fold lower than that to Gb3Cer. But it did not react with other structurally-related
glycolipids, such as LacCer (Galβ1-4Glcβ1-1′Cer), Gg3Cer, Gg4Cer, Gb4Cer (GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1′Cer), galactosylparagloboside
(Galα1-3Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer), sulfatide (HSO3-3Galβ1-1′Cer), other gangliosides (GM3, GM2, GM1a, GD1a and
GT1b), or P1 antigen (Galα1-4Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer) among neutral glycolipids prepared from P1 phenotype red
blood cells. Furthermore, TU-1 reacted with viable lymphoma cells, such as human Burkitt lymphoma cell line, Daudi, and Epstein-Barr
virus (EBV)-transformed B cells by the immunofluorescence method, and also with germinal centre B cells in human tonsil and
vessel endothelial cells in human thymus histochemically. These results indicate that TU-1 is a monoclonal antibody directed
against Gb3Cer/CD77 antigen and can be utilized as a diagnostic reagent for Burkitt's lymphoma and also for detection of the
blood group Pk antigen in glycolipid extracts of erythrocytes. Abbreviations: ATL, adult T-cell leukaemia; BSA, bovine serum
albumin; Cer, ceramide; DPPC, L-α-dipalmitoylphosphatidylcholine; EBV, Epstein-Barr virus; FCS, fetal calf serum; GalCer,
Galβ1-1′Cer; GlcCer, Glcβ1-1′Cer; LacCer, Galβ1-4Glcβ1-1′Cer; Gb3Cer, Galα1-4Galβ1-4Glcβ1-1′Cer; Iyso-Gb3Cer, Galα1-4Galβ1-4Glc1-1′Sph;
Gb4Cer, GalNAcβ1-3Galα1-4Galβ1-4Glc1-1′Cer; galactosylparagloboside, Galα1-3Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer; Gg3Cer, GalNAcβ1-4Galβ1-4Glcβ1-1′Cer;
Gg4Cer, Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1′Cer; GM3, Neu5Acα2-3Galβ1-4Glcβ1-1′Cer; GM2, GalNAcβ1-4(Neu5Acα2-3) Galβ1-4Glcβ1-1′Cer;
GM1a, Galβ1-3GalNAcβ1-4(Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GD1a, Neu5Acα2-3Galβ1-3GalNAcβ1-4(Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GD1b,
Galβ1-3GalNAcβ1-4(Neu5Acα2-8Neu5Acα2-3)Galβ1-4Glcβ1-1′Cer; GT1b, Neu5Acα2-3Galβ1-3GalNAcβ1-4(Neu5Acα2-8Neu5Acα2-3) Galβ1-4Glcβ1-1′Cer;
HRP, horseradish peroxidase; LDH, lactate dehydrogenase; MAb, monoclonal antibody; MPL, monophosphoryl lipid A; P1 antigen,
Galα1-4Galβ1-4GlcNAcβ1-3Galβ1-4Glcβ1-1′Cer; PVP, polyvinylpyrolidone; Sph, sphingosine; sulfatide, HSO3-Galβ1-1′Cer; TDM,
trehalose dimycolate; TLC, thin-layer chromatography
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
4.
Perspectives on the significance of altered glycosylation of glycoproteins in cancer 总被引:13,自引:0,他引:13
No abstract Abbreviations: Sia, sialic acid, type unspecified; Tn antigen, GalNAcα 1-O-Ser/Thr; T antigen, Galβ1-3GalNAcα-O-Ser/Thr;
Sialyl LewisX, Siaα2-3Galβ1-4(Fucα1-3)GlcNAc; Sialyl Lewisa, Siaα2-3Galβ1-3(Fucα1-4)GlcNAc; Sialyl-Tn antigen, Siaα2-6GalNAcα1-O-Ser/Thr;
FucT, fucosyltransferase; ST, sialyltransferase.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
5.
Hisashi Ashida Hayato Ozawa Kiyotaka Fujita Shun’ichi Suzuki Kenji Yamamoto 《Glycoconjugate journal》2010,27(1):125-132
Endo-α-N-acetylgalactosaminidase catalyzes the release of Galβ1-3GalNAc from the core 1-type O-glycan (Galβ1-3GalNAcα1-Ser/Thr) of mucin glycoproteins and synthetic p-nitrophenyl (pNP) α-linked substrates. Here, we report the enzymatic syntheses of core 1 disaccharide-containing glycopeptides using the
transglycosylation activity of endo-α-N-acetylgalactosaminidase (EngBF) from Bifidobacterium longum. The enzyme directly transferred Galβ1-3GalNAc to serine or threonine residues of bioactive peptides such as PAMP-12, bradykinin,
peptide-T and MUC1a when Galβ1-3GalNAcα1-pNP was used as a donor substrate. The enzyme was also found to catalyze the reverse-hydrolysis reaction. EngBF synthesized
the core 1 disaccharide-containing oligosaccharides when the enzyme was incubated with either glucose or lactose and Galβ1-3GalNAc
prepared from porcine gastric mucin using bifidobacterial cells expressing endo-α-N-acetylgalactosaminidase. Synthesized oligosaccharides are promising prebiotics for bifidobacteria. 相似文献
6.
Seven analogues of p-nitrophenyl T-antigen [Galβ(1→3)GalNAcα(1→O)PNP] have been synthesized as potential substrates for elucidation of the substrate specificity of endo-α-N-acetylgalactosaminidase. These compounds, which are commercially unavailable, include: GlcNAcβ(1→3){GlcNAcβ(1→6)}GalNAcα(1→O)PNP [core 4 type], GalNAcα(1→3)GalNAcα(1→O)PNP [core 5 type], GlcNAcβ(1→6)GalNAcα(1→O)PNP [core 6 type], GalNAcα(1→6)GalNAcα(1→O)PNP [core 7 type], Galα(1→3)GalNAcα(1→O)PNP [core 8 type], Glcβ(1→3)GalNAcα(1→O)PNP and GalNAcβ(1→3)GalNAcα(1→O)PNP. The assembly of these synthetic probes was accomplished efficiently, based on di-tert-butylsilylene(DTBS)-directed α-galactosylation as a key reaction. 相似文献
7.
Wu WC Lai CC Liu JH Singh T Li LM Peumans WJ Van Damme EJ Wu AM 《Neurochemical research》2006,31(5):619-628
Carbohydrate structures between retinal neurons and retinal pigment epithelium (RPE) play an important role in maintaining the integrity of retinal adhesion to underlying RPE, and in retinal detachment pathogenesis. Since relevant knowledge is still in the primary stage, glycotopes on the adult retina of mongrel canines (dog), micropigs and Sprague-Dawley rats were examined by lectino-histochemistry, using a panel of 16 different lectins. Paraffin sections of eyes were stained with biotinylated lectins, and visualized by streptavidin-peroxidase and diaminobenzidine staining. Mapping the affinity profiles, it is concluded that: (i) all sections of the retina reacted well with Morniga M, suggesting that N-linked glycans are present in all layers of the retina; (ii) no detectable human blood group ABH active glycotopes were found among retinal layers; (iii) outer and inner segments contained glycoconjugates rich in ligands reacting with T
α (Galβ1–3GalNAcα1-Ser/Thr) and Tn (GalNAcα1-Ser/Thr) specific lectins; (iv) cone cells of retina specifically bound peanut agglutinin (PNA), which recognizes T
α residues and could be used as a specific marker for these photoreceptors; (v) the retinas of rat, dog and pig, had a similar binding profile but with different intensity; (vi) each retinal layer had its own binding characteristic. This information may provide useful background knowledge for normal retinal physiology and miscellaneous retinal diseases, including retinal detachment (RD) and age-related macular degeneration (ARMD). 相似文献
8.
Jeschke U Karsten U Wiest I Schulze S Kuhn C Friese K Walzel H 《Histochemistry and cell biology》2006,126(4):437-444
Galectin-1 (gal-1), a member of the mammalian β-galactoside-binding proteins, recognizes preferentially Galβ1-4GlcNAc sequences of several cell surface oligosaccharides. We demonstrate histochemically that the lectin recognizes appropriate glycotopes on the syncytiotrophoblast and extravillous trophoblast layer from second trimester human placenta and on BeWo chorion carcinoma cells. Gal-1 binding to BeWo cells was diminished by the Thomsen–Friedreich (TF)-disaccharide (Galβ1-3GalNAc-) conjugated to polyacrylamide (TF–PAA). Gal-1 also inhibited BeWo cell proliferation in a concentration-dependent manner. Similar antiproliferative effects were also observed with an anti-TF monoclonal antibody (mAb, A78-G/A7). Therefore, we conclude that ligation of Galβ1-4GlcNAc and Galβ1-3GalNAc epitopes on BeWo cells may have regulatory effects on cell proliferation. 相似文献
9.
Thomsen-Friedenreich-related carbohydrate antigens in normal adult human tissues: a systematic and comparative study 总被引:5,自引:2,他引:3
Yi Cao Peter Stosiek Georg F. Springer Uwe Karsten 《Histochemistry and cell biology》1996,106(2):197-207
A broad variety of normal human tissues were examined for the expression of Thomsen-Friedenreich (TF)-related histo-blood
group antigens. TF (Galβ1-3GalNAcα1-R), Tn (TF precursor, GalNAcα1-R), sialosyl-Tn (NeuAcα2-6GalNAcα1-R), considered to be useful in cancer diagnosis and immunotherapy, and sialosyl-TF, the cryptic form of TF. These antigens
or, more correctly, glycotopcs, were determined by immunohistochemistry with at least two monoclonal antibodies (mAbs) each
(except sialosyl-TF) as well as by lectin histochemistry. For a better dissection of sialosyl-TF and TF glycotopes, tissue
sections were pretreated with galactose oxidase or the galactose oxidase-Schiff sequence. Staining with mAbs appeared to be
more restricted than with the lectins used. Distribution patterns among normal epithelia were different for all four antigens.
These antigens were also detected in some non-epithelial tissues. They can be classified in the following sequence according
to the frequency of their occurrence in normal tissues: sialosyl-TF> >sialosyl-Tn>Tn>TF. Most of the positively staining sites
for TF, Tn, and sialosyl-Tn are located in immunologically privileged areas. The complex results obtained with anti-TF mAbs
(after treatment of the tissue sections with sialidase fromVibrio cholerae) and the lectins amaranthin and jacalin revealed a differential distribution of the subtypes of sialosyl-TF [NeuAcα2-3Galβ1-3GalNAcα1-R and Galβ1-3 (NeuAcα2-6)GalNAcα1-R] in normal human tissues. From our data it can be inferred that TF, Tn, and sialosyl-Tn are promising targets for a
cancer vaccine. 相似文献
10.
Johannes Muthing 《Glycoconjugate journal》1997,14(2):241-248
The gangliosides GM1b, GalNAc-GM1b and GD1α are typical compounds of concanavalin A stimulated splenic T lymphoblasts of CBA/J
inbred mice. Their structural characterization has been described in previous studies. The intention of this work was the
comparative TLC immunostaining analysis of the glycosphingolipid composition of lectin stimulated splenic T lymphoblasts obtained
from six genetically different inbred mouse strains. The strains examined were AKR, BALB/c, C57BL/6, CBA/J, DBA/2 and WHT/Ht,
which are commonly used for biochemical and immunological studies. The neutral glycosphingolipid GgOse4Cer, the precursor
for GM1b-type gangliosides, was expressed by all six strains investigated. AKR, C57BL/6 and DBA/2 showed high and BALB/c,
CBA/J and WHT/Ht diminished expression in T lymphoblasts, based on single cell calculation. The gangliosides GM1b and GalNAc-GM1b,
elongation products of GgOse4Cer, displayed strain-specific differences in their intensities, which were found to correlate
with the intensities of GgOse4Cer expression of the same strains. Concerning sialic acid substitution of gangliosides, GM1b
and GalNAc-GM1b predominantly carry N-acetylneuraminic acid, whereas choleragenoid receptors GM1a and Gal-GalNAc-GM1b, which
are also expressed by all six strains, are characterized by dominance of N-glycolylneuraminic acid. Two highly polar gangliosides, designated with X and Y, which have not been previously recognized
in murine lymphoid tissue, were detected by positive anti-GalNAc-GM1b antibody and choleragenoid binding, respectively. Both
gangliosides were restricted to AKR, DBA/2 and C57BL/6 mice. The other three strains BALB/c, CBA/J and WHT/Ht are lacking
these structures. In summary, the GM1b-type pathway is quite active in all six strains analysed in this study. Strain-specific
genetic variations in T lymphoblast gangliosides were observed with the occurrence of gangliosides X and Y. This study and
data from other groups strongly indicate for GM1b-type gangliosides a functional association with T cell activation and leukocyte
mediated reactions. Abbreviations: ConA, concanavalin A; GSL(s), glycosphingolipid(s); HPTLC, high-performance thin-layer
chromatography; NeuAc, N-acetylneuraminic acid; NeuGc, N-glycolylneuraminic acid. The designation of the following glycosphingolipids
follows the IUPAC-IUB recommendations (1977) [48] and the ganglioside nomenclature system of Svennerholm [49] for GM1a-type
gangliosides. Glucosylceramide or GlcCer, Glcβ1-1Cer; lactosylceramide or LacCer, Galβ1-4Glcβ1-1Cer; gangliotriaosylceramide
or GgOse3Cer or Gg3, GalNAcβ1-4Galβ1-4Glcβ1-1Cer; gangliotetraosylceramide or GgOse4Cer or Gg4, Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1Cer;
gangliopentaosylceramide or GgOse5Cer, GalNAcβ1-4Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1Cer; gangliohexaosylceramide or GgOse6Cer,
Galβ1-3GalNAcβ1-4Galβ1-3GalNAcβ1-4Galβ1-4Glcβ1-1Cer. GM3, II3NeuAc-LacCer; GM1 or GM1a, II3NeuAc-GgOse4Cer; GM1b, IV3NeuAc-GgOse4Cer;
GalNAc-GM1b, IV3NeuAc-GgOse5Cer; GD1a, IV3NeuAc, II3NeuAc-GgOse4Cer; GD1b, II3(NeuAc)2-GgOse4Cer; GD1c, IV3(NeuAc)2-GgOse4Cer;
GD1α, IV3NeuAc, III6NeuAc-GgOse4Cer. Only NeuAc-substituted gangliosides are presented in this list of abbreviations
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
11.
Novel oligosaccharide has suppressive activity against human leukemia cell proliferation 总被引:1,自引:0,他引:1
Hosomi O Misawa Y Takeya A Matahira Y Sugahara K Kubohara Y Yamakura F Kudo S 《Glycoconjugate journal》2009,26(2):189-198
Various oligosaccharides containing galactose(s) and one glucosamine (or N-acetylglucosamine) residues with β1–4, α1–6 and β1–6 glycosidic bond were synthesized; Galβ1–4GlcNH2, Galα1–6GlcNH2, Galα1–6GlcNAc, Galβ1–6GlcNH2, Galβ1–4Galβ1–4GlcNH2 and Galβ1–4Galβ1–4GlcNAc. Galα1–6GlcNH2 (MelNH2) and glucosamine (GlcNH2) had a suppressive effect on the proliferation of K562 cells, but none of the other saccharides tested containing GlcNAc
showed this effect. On the other hand, the proliferation of the human normal umbilical cord fibroblast was suppressed by none
of the saccharides other than GlcNH2. Adding Galα1–6GlcNH2 or glucosamine to the culture of K562 cell, the cell number decreased strikingly after 72 h. Staining the remaining cells
with Cellstain Hoechst 33258, chromatin aggregation was found in many cells, indicating the occurrence of cell death. Furthermore,
all of the cells were stained with Galα1–6GlcNH-FITC (MelNH-FITC). Neither the control cells nor the cells incubated with
glucosamine were stained. On the other hand, when GlcNH-FITC was also added to cell cultures, some of them incubated with
Galα1–6GlcNH2 were stained. The difference in the stainability of the K562 cells by Galα1–6GlcNH-FITC and GlcNH-FITC suggests that the
intake of Galα1–6GlcNH2 and the cell death induced by this saccharide is not same as those of glucosamine. The isolation of the Galα1–6GlcNH2 binding protein was performed by affinity chromatography (melibiose-agarose) and LC-MS/MS, and we identified the human heterogeneous
ribonucleoprotein (hnRNP) A1 (34.3 kDa) isoform protein (30.8 kDa). The hnRNP A1 protein was also detected from the eluate(s)
of the MelNH-agarose column by the immunological method (anti-hnRNP-A1 and HRP-labeled anti-mouse IgG (γ) antibodies). 相似文献
12.
In cancer, mucins are aberrantly O-glycosylated, and consequently, they express tumor-associated antigens such as the Tn determinant (alpha-GalNAc-O-Ser/Thr). As compared with normal tissues, they also exhibit a different pattern of expression. In particular, MUC6, which is normally expressed only in gastric tissues, has been detected in intestinal, pulmonary, colorectal, and breast carcinomas. Recently, we have shown that the MCF7 breast cancer cell line expresses MUC6-Tn glycoproteins in vivo. Cancer-associated mucins show antigenic differences from normal mucins, and as such, they may be used as potential targets for immunotherapy. To develop anticancer vaccines based on the Tn antigen, we prepared several MUC6-Tn glycoconjugates. To this end, we performed the GalNAc enzymatic transfer to two recombinant MUC6 proteins expressed in Escherichia coli, using UDP-N-acetylgalactosamine: polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-Ts), which catalyze in vivo the Tn antigen synthesis. We used either a mixture of ppGalNAc-Ts from MCF7 breast cancer cell extracts or a recombinant ppGalNAc-T1. In both cases, we achieved the synthesis of MUC6-Tn glycoconjugates at a semi-preparative scale (mg amounts). These glycoproteins displayed a high level of Tn antigens, although the overall density depends on both enzyme source and protein acceptor. These MUC6-Tn glycoconjugates were recognized by two anti-Tn monoclonal antibodies that are specific to human cancer cells. Moreover, the MUC6-Tn glycoconjugate glycosylated using MCF7 extracts as the ppGalNAc-T source was able to induce immunoglobulin G (IgG) antibodies that recognized a human tumor cell line. In conclusion, the large-scaled production of MUC6 with tumor-relevant glycoforms holds considerable promise for developing effective anticancer vaccines, and further studies of their immunological properties are warranted. 相似文献
13.
Cappello S Liu NX Musselli C Brezicka FT Livingston PO Ragupathi G 《Cancer immunology, immunotherapy : CII》1999,48(9):483-492
Fucosyl-GM1 (Fuc-GM1) [Fucα1 → 2Galβ1 → 3GalNAcβ1 → 4(NeuAcα2-3)Galβ1 → 4Glcβ1 → O-Cer] is a small-cell-lung-cancer (SCLC)-associated ganglioside initially defined by the murine monoclonal antibody F12. On
the basis of its known distribution, Fuc-GM1 is a potential target for active immunotherapy in SCLC patients. Fuc-GM1 has
been extracted and purified from bovine thyroid. The immunogenicity of Fuc-GM1 was tested in mice either alone, mixed with
carrier protein keyhole limpet hemocyanin (KLH) or covalently linked with KLH, plus immunological adjuvant QS-21. The Fuc-GM1-KLH
conjugate plus QS-21 adjuvant was found to be optimal. It induced consistent IgM and IgG enzyme-linked immunosorbent assay
(ELISA) titers against Fuc-GM1. These antibodies were strongly reactive with the strongly Fuc-GM1-positive rat hepatoma cell
line H4-II-E, and they were moderately reactive with the moderately positive human SCLC cell line H146 by flow cytometry and
complement-mediated lysis. Both ELISA and fluorescence-activated cell sorting (FACS) reactions were inhibited with Fuc-GM1or
H4-II-E but not with the structurally related ganglioside GM1 or Fuc-GM1-negative colon cancer cell line LS-C. On the basis
of these results, a vaccine comprising Fuc-GM1-KLH plus QS-21 is being prepared for testing in patients with SCLC.
Received: 25 March 1999 / Accepted: 5 August 1999 相似文献
14.
Four unidentified acidic glycolipids (X3-X6) were isolated from the kidney of the Pacific salmon on an anion exchange column
and by high performance liquid chromatography using a silica bead (Iatrobeads) column. Based on methylation analysis, chemical
and enzymatic degradation, proton nuclear magnetic resonance spectroscopy and mass spectrometry, the glycon structure of X5
and X6 was identified as a unique disialosyl fucosyl-N-acetylgalactosaminyl ganglio-N-tetraose:
Fucα3GalNAcβ3Galβ3GalNAcβ4[NeuAcα8NeuAcα3] Galβ4Glcβ1Cer. NMR showed that X3 and X4 were analogues of X5 and X6 and contained
O-acetyl groups on C4 of the outer N-acetylneuraminic acid, first disialosyl gangliosides containing 4-O-acetyl-N-acetylneuraminic acid. The ceramides of X3 and X5 contained predominantly C24: 1, and X4 and X6 contained saturated fatty
acids (C14: 0, C16: 0 and C18: 0), whereas the long chain base was exclusively sphingenine. The concentrations of X3 and X4
were 0.13 and 0.16 nmol/g of kidney respectively and those of X5 and X6, were 0.07 nmol/g each. 相似文献
15.
Matrix-assisted laser desorption/ionization quadrupole ion trap time-of-flight mass spectrometry (MALDI-QIT-TOF MS) was used
to analyze three pyridylamino (PA)-fucosyloligosaccharides isolated from human milk: lacto-N-fucopentaose (LNFP) I [Fucα1-2Galβ1-3GlcNAcβ1-3Galβ1-4Glc-PA],
LNFP II [Galβ1-3(Fucα1-4)GlcNAcβ1-3Galβ1-4Glc-PA], and LNFP III [Galβ1-4(Fucα1-3)GlcNAcβ1-3Galβ1-4Glc-PA]. These oligosaccharides
are linkage isomers. MALDI-QIT-TOF MS provides MSn spectra, which we used to characterize these PA-oligosaccharides. MS/MS/MS analysis of the non-reducing end tri-saccharide
ions generated by MS/MS was able to distinguish these oligosaccharide isomers. The MALDI-QIT-TOF MS is a very convenient and
rapid method, therefore, it would be useful for high throughput structural analyses of various types of pyridylaminated oligosaccharide
isomers. 相似文献
16.
Peter R. Andreana Przemyslaw Kowal Adam J. Janczuk Peng George Wang 《Glycoconjugate journal》2003,20(2):107-118
Galactose oxidase (EC 1.1.3.9, GAO) was used to convert the C-6′ OH of Galβ(1 → 4)Glcβ–OBn (5) to the corresponding hydrated
aldehyde (7). Chemical modification, through dehydratative coupling and reductive amination, gave rise to a small library
of Galβ(1 → 4)Glcβ–OBn analogues (9a–f, 10, 11). UDP-[6-3H]Gal studies indicated that α1,3-galactosyltransferase recognized the C-6′ modified Galβ(1 → 4)Glcβ–OBn analogues (9a–f,
10, 11). Preparative scale reactions ensued, utilizing a single enzyme UDP-Gal conversion as well as a dual enzymatic system
(GalE and α1,3GalT), taking full advantage of the more economical UDP-Glc, giving rise to compounds 6, 15–22. Galα(1 → 3)Galβ(1
→ 4)Glcβ–OBn trisaccharide (6) was produced on a large scale (2 g) and subjected to the same chemoenzymatic modification as
stated above to produce C-6″ modified derivatives (23–30). An ELISA bioassay was performed utilizing human anti-αGal antibodies
to study the binding affinity of the derivatized epitopes (6, 15–30). Modifications made at the C-6′ position did not alter
the IgG antibody's ability to recognize the unnatural epitopes. Modifications made at the C-6″ position resulted in significant
or complete abrogation of recognition. The results indicate that the C-6′ OH of the αGal trisaccharide epitope is not mandatory
for antibody recognition. Published in 2004.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Characterization of serum {beta}-glucuronyltransferase involved in chondroitin sulfate biosynthesis 总被引:3,自引:3,他引:0
Kitagawa Hiroshi; Ujikawa Miho; Tsutsumi Kae; Tamura Jun-ichi; Neumann Klaus W.; Ogawa Tomoya; Sugahara Kazuyuki 《Glycobiology》1997,7(7):905-911
We studied a glucuronyltransferase involved in chondroitin sulfate(CS) biosynthesis in a preparation obtained from fetal bovineserum by heparin-Sepharose affinity chromatography. This enzymetransferred GlcA from UDP-GlcA to the nonreducing GalNAc residuesof polymeric chondroitin. It required Mn2+ for maximal activityand showed a sharp pH optimum between pH 5.5 and 6.0. The apparentKm value of the glucuronyltransferase for UDP-GlcA was 51 µM.The specificity was investigated using structurally definedacceptor substrates, which consisted of chemically synthesizedtri-, penta-, and heptasaccharide-serines and various odd-numberedoligosaccharides with a GalNAc residue at the nonreducing terminus,prepared from chondroitin and CS by chondroitinase ABC digestionfollowed by mercuric acetate treatment. The enzyme utilizeda heptasaccharide-serine GalNAcß1-4GlcAß1-3GalNAcß1-4GlcAß1-3Galß1-3Galß1-4Xylß1-O-Serand a pentasaccharide-serine GalNAcß 4GlcAß1-3Galß1-3Galß1-4Xylß1-O-Seras acceptors. In contrast, neither a trisaccharide-serine Galß1-3Galß1-4Xylß1-O-Sernor an 相似文献
18.
To elucidate the mechanism underlying the hydrolysis of the GalNAcβ1→4Gal linkage in ganglioside GM2 [GalNAcβ1→4(NeuAcα2→3)Galβ1→4Glcβ1→1′
Cer] by β-hexosaminidase A (Hex A) with GM2 activator protein, we designed and synthesized two kinds of GM2 linkage analogues—6′-NeuAc-GM2
and α-GalNAc-GM2. In this paper, the efficient and systematic synthesis of these GM2 analogues was described. The highlight
of our synthesis process is that the key intermediates, newly developed sialyllactose derivatives, were efficiently prepared
in sufficient quantities; these derivatives directly served as highly reactive glycosyl acceptors and coupled with GalNTroc
donors to furnish the assembly of GM2 tetrasaccharides in large quantities. 相似文献
19.
Yu LG 《Glycoconjugate journal》2007,24(8):411-420
The oncofetal Thomsen–Friedenreich carbohydrate antigen (Galβ1-3GalNAcα1-Ser/Thr TF or T antigen) is a pan-carcinoma antigen
highly expressed by about 90% of all human carcinomas. Its broad expression and high specificity in cancer have attracted
many investigations into its potential use in cancer diagnosis and immunotherapy. Over the past few years increasing evidence
suggests that the increased TF occurrence in cancer cells may be functionally important in cancer progression by allowing
increased interaction/communication of the cells with endogenous carbohydrate-binding proteins (lectins), particularly the
members of the galactoside-binding galectin family. This review focuses on the recent progress in understanding of the regulation
and functional significance of increased TF occurrence in cancer progression and metastasis. 相似文献
20.
G. Ya. Wiederschain O. Koul N. V. Bovin N. E. Nifant’ev R. McCluer 《Russian Journal of Bioorganic Chemistry》2000,26(6):403-406
The substrate specificity of fucosyltransferase (FT) from rat forebrain and cerebellum was studied using synthetic acceptors.
Of 16 acceptors tested, only those containing the Galβ1-4GlcNAcβ1-R fragment were subjected to enzymic fucosylation. The isomer
with a 1–3 bond as well as lactose and oligosaccharides with an additional Neu5Ac residue attached to Gal or a Fuc residue
attached to GlcNAc were not fucosylated, whereas Fucα1-2Galβ1-4GlcNAc displayed the same substrate properties as Galβ1-4GlcNAc.
FT from the cerebellum and forebrain was shown to have a specificity similar to that of mammalian FT IV. The activity of the
cerebellum FT with all types of substrates was higher than that of FT isolated from the forebrain, the specificity profiles
being similar.
This communication is dedicated to the 70th birthday of Prof. A.Ya. Khorlin. 相似文献