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Y Kushi

Publications and source records attributed to Y Kushi.

At least 37 records · Page 2Linked to original sources
PubMed1989

Analysis of underivatized glycosphingolipids by high-performance liquid chromatography/atmospheric pressure ionization mass spectrometry.

Analytical conditions for underivatized glycosphingolipids by using high-performance liquid chromatography atmospheric pressure ionization mass spectrometry (HPLC/API-MS) were investigated. The analysis was performed by using an ordinary reversed-phase column (4.6 X 150 or 4.6 X 250 mm) at a flow rate of 1 ml/min. The glycosphingolipids could be characterized from the HPLC/API-MS in terms of molecular weight, ceramide composition, and partial oligosaccharide sequence. In order to obtain an adequate spectrum the amount of material needed is in the range of a few micrograms of lipid. By selected ion monitoring the sensitivity of the method allowed characterization of only 60 ng of glycosphingolipid. The method will be very useful in the characterization of small quantities of glycosphingolipids from biological samples.

Atmospheric Pressure↗
PubMed1989

Mono-sulfated globopentaosylceramide from human kidney.

A novel sulfated glycosphingolipid that belongs to the "globo-series" was isolated from human kidney. This lipid was purified from a pooled kidney preparation by chloroform/methanol extraction, mild alkaline treatment, DEAE-Sephadex and silicic acid column chromatographies, and preparative thin layer chromatography. The structure and the properties were studied by infrared spectroscopy, two-dimensional proton magnetic resonance spectroscopy, negative secondary ion mass spectrometry, solvolysis, compositional and methylation analyses, monoclonal antibodies, and sulfatide-binding proteins. From the results of the above analyses, the structure of this glycolipid was proposed to be HSO3-3Gal beta 1-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc beta 1-1ceramide. The proton resonance at 3.93 ppm of the H-3 of the sulfated nonreducing terminal galactose of this lipid was downfield-shifted (delta 0.48 ppm), as compared with H-3 of the internal beta-galactose because of the electronegativity of the sulfate ester. This sulfated lipid reacted with a monoclonal anti-SSEA-3 (MC-631) (Kannagi, R., Cochran, N. A., Ishigami, F., Hakomori, S., Andrews, P. W., Knowles, B. B., and Solter, D. (1983) EMBO J. 2, 2355-2361), whose epitope is R-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-R', on thin layer chromatograms and solid-phase radioimmunoassay. This lipid also bound to the 125I-labeled sulfatide-binding protein, thrombospondin. The yield of this sulfated glycolipid was 0.19 nmol/g of tissue, which was about 0.09 and 0.5 mol % of galactosyl and lactosyl sulfatides in human kidney.

Chromatography, Ion Exchange↗
PubMed1989

A sulfated glucosylceramide from rat kidney.

A novel sulfated glycosphingolipid containing a sulfated glucosyl residue was isolated from rat kidney and purified to homogeneity by column chromatographies with DEAE-Sephadex and silica beads. By compositional analyses, permethylation studies, one- and two-dimensional proton magnetic resonance spectroscopy, infrared spectroscopy, negative secondary ion mass spectrometry, solvolysis, and immunostaining on thin layer chromatogram, the structure of this glycolipid was proposed to be HSO3-3Glc beta 1-1Cer (where Cer is ceramide). The ceramide portion consisted of 4-D-hydroxysphinganine as the sole long chain base, and the fatty acid consisted of predominantly tetracosanoic acid, deduced from both composition analysis and negative secondary ion mass spectrometry. The yield of glucosyl sulfatide was about 5 nmol/g of tissue, being about three times as much as that of lactosylceramide sulfate.

Animals↗
PubMed1989

Mono-sulfated globotetraosylceramide from human kidney.

A novel sulfated glycosphingolipid that belongs to "globo-series" was isolated from human kidney. This lipid was purified from a pooled kidney preparation by chloroform-methanol extraction, mild alkaline treatment, DEAE-Sephadex and silicic acid column chromatographies, and preparative TLC. The structure and the properties were studied by IR spectroscopy, proton NMR spectroscopy, negative secondary ion-mass spectrometry, solvolysis, periodate oxidation, compositional and methylation analyses, monoclonal antibodies, and a sulfatide-binding protein. From the results of the above analyses, the structure of this glycolipid was proposed to be HSO3-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-4Glc beta 1-1ceramide. This sulfated lipid reacted with a monoclonal anti-SSEA-3 (stage-specific embryonic antigen-3) (MC-631) (Kannagi, R., Cochran, N.A., Ishigami, F., Hakomori, S., Andrews, P.W., Knowles, B.B., & Solter, D. (1983) EMBO J. 2, 2355-2361), whose epitope is R-3GalNAc beta 1-3Gal alpha 1-4Gal beta 1-R', on TLC and solid-phase radioimmunoassay. This lipid also bound to the 125I-labeled sulfatide-binding protein, thrombospondin. The yield of this sulfated glycolipid was 34 pmol/g of tissue, which was about 0.028, 0.16, and 18 mol% of galactosyl- and lactosylceramide sulfates, and globopentosylceramide sulfate (Nagai, K.-i., Roberts, D.D., Toida, T., Matsumoto, H., Kushi, Y., Handa, S., & Ishizuka, I. (1989) J. Biol. Chem. 264, in press), respectively, in human kidney.

Animals↗
PubMed1988

Direct analysis of glycolipids on thin-layer plates by matrix-assisted secondary ion mass spectrometry: application for glycolipid storage disorders.

The lipids accumulated in organs of patients with Gaucher's, Tay-Sachs, and Fabry's disease were identified by means of the combination of thin-layer chromatography and matrix-assisted secondary ion mass spectrometry. The total lipid extract of each lipidosis tissue was chromatographed on a TLC plate and then analyzed directly by mass spectrometry without elution of the sample from the TLC plate. The amount of material needed to obtain an adequate spectrum is in the order of a few micrograms of lipids per band for both positive and negative ion detection. By scanning the plates, mass spectral and chromatographic information can be obtained simultaneously, which was shown to be useful for the qualitative identification of the components on the plates.

Chromatography, Thin Layer↗
PubMed1988

Identification of 2-azelaoylphosphatidylcholine as one of the cytotoxic products generated during oxyhemoglobin-induced peroxidation of phosphatidylcholine.

Cytotoxic product(s), which are responsible for inducing the release of acetylcholinesterase-enriched vesicles from human erythrocytes and cell lysis, are generated when 1-saturated-2-polyunsaturated glycerophosphocholine was incubated with oxyhemoglobin (Itabe, H., Kobayashi, T. and Inoue, K. (1988) Biochim. Biophys. Acta 961, 13-21). To identify the products, a model compound, 1-O-octadecyl-2-linoleoylglycerophosphocholine was incubated with oxyhemoglobin. The oxidation products were isolated by both straight-phase and reverse-phase HPLC. The products, which were responsible for inducing erythrocyte membrane damage, were analyzed by secondary ion mass spectrometry and 1H-NMR. One of the cytotoxic products isolated was identified as 1-O-octadecyl-2-azelaoylglycerophosphocholine. Methyl esterification of the product confirmed the proposed structure.

Chemical Phenomena↗
PubMed1985

Secondary ion mass spectrometry for sulfoglycolipids: application of negative ion detection.

A series of underivatized sulfoglycolipids (SM4g, lyso-SM4g, SM4s, SM3, SM2, SB2, and SB1a) from various tissues were analyzed by both positive (POS-SI-MS) and negative (NEG-SI-MS) secondary ion mass spectrometry. By POS-SI-MS were detected the molecular ions of sulfoglycolipids in the form with sodium or potassium together with some fragment ions useful for the carbohydrate sequence determination. The analysis of monosulfogangliotriaosyl- or monosulfogangliotetraosylceramide and bis-sulfoglycolipid was difficult due to noise in the high mass region. On the other hand, NEG-SI-MS of sulfoglycolipids gave more intense signals from molecular ion of (M-H)- for monosulfoglycolipids and [M-H+Na)-H)- for bis-sulfoglycolipid. Many fragment ions useful for the elucidation of the carbohydrate sequences were also obtained with significant intensities. The fragmentation was assessed to occur at the glycosidic linkages to form ions of the oligosaccharides with or without ceramide. These ions were useful for sugar sequencing and also for distinguishing the differences in the position of the sulfate group. The intensities of saccharide ions without sulfate were lower than those with sulfates. In the case of SB2 and SB1a, containing 2 mol of sulfate ester groups, the molecular ion was detected as [M-H+Na)-H)-. Also, fragment ions with 2 mol of sulfate were detected as the sodium-additive form. It was concluded that NEG-SI-MS is a very useful technique for the structural elucidation of higher sulfoglycolipids.

Animals↗
PubMed1985

Direct analysis of lipids on thin layer plates by matrix-assisted secondary ion mass spectrometry.

A simple and rapid method for the analysis of lipids on a thin layer chromatography (TLC) plate by matrix-assisted secondary ion mass spectrometry (SI-MS) is reported. Analysis was performed without elution of the sample from the TLC plate. Mass spectra obtained by this method are free from interference due to the TLC plate absorbent and reagents used for the detection of the spots. About 1 micrograms of lipids applied on a TLC plate can be analyzed by this method. On scanning the plate, mass chromatograms of each lipid were obtained based on its migration distance along the plate.

Chromatography, Thin Layer↗
PubMed1984

Application of field desorption and secondary ion mass spectrometry for glycolipid analysis.

Field desorption (FD) and secondary ion mass spectrometry (SI-MS) mass spectra of several glycolipids are presented to demonstrate their potential for the analysis of glycolipids. FD and SI-MS give useful information on molecular weight, ceramide structure and sugar sequence. In general, FD provides clearer fragment ion peaks for the analysis of sugar sequence than SI-MS. For underivatized acidic glycolipids such as gangliosides, sulfatide and seminolipid, SI-MS provides quasimolecular ions which are hardly produced by FD. In contrast to underivatized gangliosides, permethylated samples give molecular ion species of high intensity in both FD and SI-MS, but no fragment ions pertinent to carbohydrate sequence could be observed in FD spectra. SI-MS spectra of permethylated samples provide good information on sugar chain structure. Thus FD and SI-MS mass spectra complement each other, and the combination of these ionization methods will provide powerful tools for glycolipid analysis.

Animals↗
PubMed1983

Secondary ion mass spectra of neutral sphingoglycolipids.

Secondary ion mass spectra of underivatized neutral sphingoglycolipids are presented. In the spectra of mono- and di-glycosylceramide, ions (M + H)+ and (M + H-H2O)+ were observed as relatively intense quasimolecular ions, whereas in the spectra of higher glycolipids, the quasimolecular ion species were predominantly (M + Na)+. Ions due to the ceramide moiety were observed as intense peaks comparable to quasimolecular ions. Ions derived from the fragments cleaved at the glycosidic linkages were hardly detected due to their low intensities. In general, secondary ion mass spectrometry provides good stable spectra for a long time during analysis.

Glycosphingolipids↗
PubMed1983

Comparative study of acidic glycosphingolipids by field desorption and secondary ion mass spectrometry.

Acidic glycosphingolipids were analyzed by field desorption (FD-MS) and secondary ion mass spectrometry (SI-MS) using the primary ion Xe+ with a glycerol matrix. In the analysis of underivatized gangliosides by FD-MS, the fragment corresponding to the asialo residue resulting from the cationized cluster ion (M + Na)+ was the base peak, and ions due to cleavage at the glycosidic linkages were detected, as in the neutral glycosphingolipids. In the case of sulfatide, the ceramide fragment showed the highest intensity in the spectrum. In SI-MS spectra of acidic glycosphingolipids, (M + Na)+, (M + 2Na-H)+, and (M + K)+ were continuously detected as relatively high intensity ions during analysis of gangliosides and sulfatide. Other ions were mostly similar to those obtained by FD-MS. In FD-MS spectra of permethylated gangliosides, the cationized molecular ion (M + Na)+ was the base peak, and fragment ions due to asialo gangliosides were prominent. Other peaks were hard to detect. In SI-MS, molecular ions (M + H)+ and (M + H-32)+ and other ions due to cleavage of the glycosidic linkages were clearly detected. In this case, the sensitivity was greatly improved. Ions due to the non reducing end sugars were clearly detected, because of the relatively low intensity of ion peaks due to the glycerol matrix. It is concluded that the combination with FD-MS and SI-MS is particularly useful for the determination of molecular weight, sugar sequence and ceramide structure with sample amounting to only a few micrograms order.

Animals↗
PubMed1982

Application of field desorption mass spectrometry for the analysis of sphingoglycolipids.

Simple molecular species of intact ceramide mono-, di-, tri-, tetra-, and pentasaccharides purified by reversed phase high-performance liquid chromatography (HPLC) were analyzed by field desorption mass spectrometry (FD-MS). The analysis of sphingoglycolipids without chemical derivatization by FD-MS not only provides molecular information but also significant characteristic fragments for structural determination due to the cleavage of glycosidic bonds. These ions, therefore, give information on the molecular species of sphingoglycolipids and sugar sequences of their oligosaccharides. Intact GL1a, GL2a, and an equimolar mixture of GL1a and GL2a were also analyzed by FD-MS. In the spectra, the ions, (M + H)+, (M + Na)+, and (M + H- H2O)+, were observed as high intensive ions and different molecular species ions thereafter could be identified in all spectra. The FD-MS method is particularly useful in structural studies of glycolipids from natural sources.

Chromatography, High Pressure Liquid↗
PubMed1982

Structural study on gangliosides from rat liver and erythrocytes.

Gangliosides were isolated from rat liver and erythrocytes by chromatography on columns of DEAE-Sephadex and Iatrobeads, and finally purified by preparative TLC. The chemical structures of the purified components were studied by carbohydrate analysis, methylation analysis, sialidase treatment, fatty acid analysis and direct mass spectrometry. In rat liver, gangliosides GM3, GM1, GD3, GD1a, GD1b, and GT1b were identified. Gangliosides in rat erythrocytes were characterized as GM1, fucosyl-GM1, and GD1a. Sialic acid was the N-acetyl type only and lignoceric acid was the main fatty acid in all components of rat liver and erythrocytes.

Animals↗