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- Breimer, Michael, 1951, et al.
(författare)
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Structural identification of two ten-sugar branched chain glycosphingolipids of blood group H type present in epithelial cells of rat small intestine.
- 1982
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Ingår i: The Journal of biological chemistry. - 0021-9258. ; 257:1, s. 50-9
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Tidskriftsartikel (refereegranskat)abstract
- Two novel blood group H-type decaglycosylceramides with a branched core saccharide have been identified in mixture in a fraction isolated from rat small intestine. They were present exclusively in the epithelial cells. The number and sequence of sugars were established by direct inlet mass spectrometry of the permethylated and LiAlH4-reduced permethylated derivatives. Gas-liquid chromatography of the products after degradation of the native and permethylated glycolipids gave the type of sugars and the binding positions. A di- and a trisaccharide were identified by mass spectrometry after degradation of the permethylated-reduced derivative. One trisaccharide had the structure (formula see text) and was therefore additional evidence for a branched structure. Treatment of the decaglycosylceramide fraction with alpha-L-fucosidase gave free fucose and an octaglycosylceramide identified by mass spectrometry. Proton NMR spectra of the permethylated and permethylated-reduced octa- and decaglycosylceramides provided evidence for the binding configurations and the localization of type 1 and type 2 sequences in the two branches. The 3-linked branch was homogeneous with a type 1 saccharide (Gal beta 1 leads to 3GlcNAc) but the 6-linked branch had both type 1 and type 2 (Gal beta 1 leads to 4GlcNAc) sequences. Two glycolipids with the following probable structures were therefore present, making up 60 and 40% of the mixture, respectively: (formula see text) The lipophilic part contained mainly trihydroxy 18:0 long chain base (phytosphingosine) and 16:0 to 24:0 nonhydroxy fatty acids.
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| 2. |
- Ångström, Jonas, 1950, et al.
(författare)
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Chemical characterization of penta-, hexa-, hepta-, octa-, and nonaglycosylceramides of rat small intestine having a globoside-like terminus.
- 1982
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Ingår i: The Journal of biological chemistry. - 0021-9258. ; 257:2, s. 682-8
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Tidskriftsartikel (refereegranskat)abstract
- A novel series of glycosphingolipids has been isolated from the nonepithelial part of rat small intestine. A mixed fraction containing 3 major components corresponding to glycolipids with 5, 6, and 7 sugars and 2 minor components with 8 and 9 sugars was characterized. The structure of the major components was deduced by mass spectrometry and proton NMR spectroscopy of nondegraded permethylated and permethylated-reduced (LiAlH4) derivatives and gas-liquid chromatography of degradation products of native, permethylated, and permethylated-reduced glycolipids. The structures of the penta-, hexa-, and hepta-glycosylceramides were found to be GalNAcp beta 1 leads to (3Galp alpha 1 leads to)2-44Galp beta 1 leads to 4Glcp beta 1 leads to 1Cer. By analogy reasoning, supported by mass spectrometry, the octa- and nonaglycosylceramides were concluded to have 1 and 2 additional internal leads to 3Galp alpha 1 leads to 3 structures, respectively. A pentaglycosylceramide fraction from another rat strain was also isolated. The NMR spectra were in agreement with 2 isomeric structures of which 1 had the internal alpha 1 leads to 4 linkage replaced by an alpha 1 leads to 3 linkage. The fatty acids of all components were nonhydroxy 16:0 to 24:0 acids with the 18:0 homologue as dominating species. The major base was sphingosine and possibly monohydroxy 18:1 base in the larger glycolipids. This is a novel series of structures with a terminal saccharide identical with isoglobotetraoxylceramide (cytolipin R). The glycosyltransferase for the terminal GalNAc beta 1 leads to 3 of cytolipin R may possibly be identical with the enzyme adding the terminal sugar of this novel series. This is supported by the presence in the same tissue of probable precursor glycolipids with 4 to 8 hexoses.
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| 3. |
- Ångström, Jonas, 1950, et al.
(författare)
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Separation and characterization of hematosides with different sialic acids and ceramides from rat small intestine. Different composition of epithelial cells versus non-epithelial tissue and of duodenum versus jejunum-ileum.
- 1981
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Ingår i: Journal of biochemistry. - 0021-924X. ; 90:4, s. 909-21
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Tidskriftsartikel (refereegranskat)abstract
- The hematosides (sialyl-lactosylceramides) of rat small intestine were separated as their acetylated derivatives. The isolated fractions were characterized by mass spectrometry and degradative methods, and the two major fractions also by NMR spectroscopy. From these results hematosides with different sialic acid and ceramide type could be assigned to thin-layer chromatographic bands. This allowed a structural interpretation of the chromatographic patterns observed for different parts of the small intestine. Thus, epithelial cells of ileum contained only hematoside with N-glycoloylneuraminic acid. Duodenum lacked this compound and instead the epithelial cells contained hematoside with N-acetylneuraminic acid. In non-epithelial tissue or both duodenum and jejunum-ileum the major hematoside had N-acetyl-neuraminic acid. The hematosides of epithelial cells had ceramide containing 18 : 0 trihydroxy base combined with 16, 20, 22, 24 : 0, and 24 : 1 hydroxy fatty acids (major part) or non-hydroxy fatty acids. In the non-epithelial hematosides the ceramide consisted of 18 : 1 dihydroxy base combined with 16, 18, 20, 22, 24 : 0, and 24 : 1 non-hydroxy fatty acids.
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| 4. |
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| 5. |
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| 6. |
- Breimer, Michael, 1951, et al.
(författare)
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Blood group type glycosphingolipids from the small intestine of different animals analysed by mass spectrometry and thin-layer chromatography. A note on species diversity.
- 1981
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Ingår i: Journal of biochemistry. - 0021-924X. ; 90:3, s. 589-609
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Tidskriftsartikel (refereegranskat)abstract
- The total non-acid glycosphingolipids were isolated from the small intestine of cat, cod-fish, guinea-pig, hen, mouse, rabbit, and two strains of rat. The samples were analyzed by thin-layer chromatography and mass spectrometry and for immunological activity. Mass spectrometry of permethylated and LiAlH4-reduced permethylated derivatives allowed the interpretation of the structures (carbohydrate sequence and ceramide composition) of up to 9 glycolipid species in one mixture. The interpretation was facilitated by a temperature programming of the direct inlet probe, leading to a successive evaporation of glycolipid species mainly according to the number of sugars. The structures concluded could in most cases be assigned to the separate bands revealed by thin-layer chromatography. Antigenic determinants proposed by the spectra were settled by immunological analysis. Thus, Forssman glycolipid was identified in cat, guinea-pig, hen and mouse, blood group A glycolipids in cat, rabbit, and rat and blood group B glycolipids in rabbit and rat. No Lewis activity was found. Certain ceramide types were demonstrated to exist preferentially in some glycolipids. Globoside and Forssman glycolipids (globo series) had a less hydroxylated ceramide (one free hydroxyl) compared to most fucolipids and other glycolipids (two or three hydroxyls). In conclusion, glycolipid patterns of intestine vary between species, and individuals of the same species.
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| 7. |
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| 8. |
- Breimer, Michael, 1951, et al.
(författare)
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Glycolipids of rat small intestine. Characterization of a novel blood group H-active triglycosylceramide.
- 1980
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Ingår i: Biochimica et biophysica acta. - 0006-3002. ; 617:1, s. 85-96
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Tidskriftsartikel (refereegranskat)abstract
- A novel blood group H-active triglycosylceramide has been isolated from rat small intestine. It was present exclusively in the epithelial cells. The structure was established by mass spectrometry, NMR spectroscopy and degradative methods to the Fucp alpha 1 leads to 2Galp beta 1 leads to 4Glcp beta 1 leads to 1Cer. The lipophilic part was made up of mainly trihydroxy base (phytosphingosine) and 16 : 0--24 : 0 fatty acids.
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| 9. |
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| 10. |
- Breimer, Michael, 1951, et al.
(författare)
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Glycosphingolipids of rat tissues. Different composition of epithelial and nonepithelial cells of small intestine.
- 1982
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Ingår i: The Journal of biological chemistry. - 0021-9258. ; 257:1, s. 557-68
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Tidskriftsartikel (refereegranskat)abstract
- The epithelial cells of rat small intestine (jejunum-ileum) were separated from their supporting stroma (residue). Total nonacid and acid glycosphingolipids were prepared from the two compartments. The acetylated nonacid glycolipids were separated into 10-12 fractions by column chromatography. These were analyzed by chromatographic methods, mass spectrometry, and proton NMR spectroscopy and compared with glycolipids isolated from whole rat small intestine. The sialic acid-containing glycosphingolipids were compared in the same way without subfractionation. At least 37 different glycosphingolipids (different carbohydrate moieties) were found, 23 in the nonepithelial residue and 17 in the epithelial cells of one rat strain. In a second rat strain, another 4 structures were detected. The glycosphingolipids of epithelial cells and nonepithelial residue were distinctly different. Glucosylceramide, lactosylceramide, and globotriaosylceramide were found in both compartments, while isoglobotriaosylceramide was restricted to the nonepithelial residue. A tetrahexosylceramide with a terminal Gal alpha 1 leads to 3 on a globotriaosylceramide core was found in both compartments as were homologues with 1 or 2 additional internal leads to 3Gal alpha 1 leads to units, but homologues with 3 or 4 additional internal Gal were only nonepithelial. Glycosphingolipids with terminal beta-GalNAc were restricted to the nonepithelial residue comprising globotetraosylceramide, isoglobotetraosylceramide, and a series of glycolipids with 5 to 9 sugars having the above-mentioned oligohexosylceramides as core structures. Fucolipids (blood group H) having 3, 5, 6, and 7 sugars and lacking amino sugars, and fucolipids with 5 and 10 sugars containing N-acetylglucosamine were restricted to the epithelial cells. Fucolipids (blood groups H and B) with 5 and 6 sugars containing N-acetylgalactosamine were restricted to the nonepithelial residue. In a 4, 6, and 12 sugars were found in the epithelial cells. N-Glycoloylneuraminosyllactosylceramide was the only ganglioside found in the epithelial cells while N-acetylneuraminosyllactosylceramide was nonepithelial together with gangliosides based on gangliotetraosylceramide and isoglobotetraosylceramide.
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