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1.
O-(alpha-D-Mannopyranosyl)-(1----2)-O-(alpha-D-mannopyranosyl)-(1----3)- O- [(alpha-D-mannopyranosyl)-(1----2)-O-(alpha-D-mannopyranosyl)-(1----6)]- O- (alpha-D-mannopyranosyl)-(1----6)-O-(beta-D-mannopyranosyl)-(1----4)-O-( 2- acetamido-2-deoxy-beta-D-glucopyranosyl)-(1----4)-2-acetamido-2-deoxy- glucopyranose, an octasaccharide fragment of high-mannose type glycan of glycoproteins, was synthesized. Crucial glycosylation of trisaccharide intermediate, benzyl O-(2,4-di-O-benzyl-beta-D-mannopyranosyl)-(1----4)-O-(2-acetamido-3,6-di -O- benzyl-2-deoxy-beta-D-glucopyranosyl)-(1----4)-2-acetamido-3,6-di-O-benz yl-2- deoxy-beta-D-glucopyranoside, was successful only with a di-O-acetyltetradeca-O-benzyl-D-mannopentaosyl chloride. The use of the corresponding hexadeca-O-acetyl-D-mannopentaosyl bromide did not give the desired product.  相似文献   

2.
Two trisaccharides, three tetrasaccharides, two pentasaccharides, one hexasaccharide, one heptasaccharide, one octasaccharide and one decasaccharide were isolated from polar bear milk samples by chloroform/methanol extraction, gel filtration, ion exchange chromatography and preparative thin-layer chromatography. The oligosaccharides were characterized by 1H-NMR as follows: the saccharides from one animal: Gal(alpha1-3)Gal(beta1-4)Glc (alpha3'-galactosyllactose), Fuc(alpha1-2)Gal(beta1-4)Glc (2'-fucosyllactose), Gal(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)Glc (B-tetrasaccharide), GalNAc(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)Glc (A-tetrasaccharide), Gal(alpha1-3)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Glc, Gal(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Gl c, Gal(alpha1-3)Gal(beta1-4)GlcNAc(beta1-3)[Gal(alpha1-3)Gal(beta1-4)Glc NAc(beta1-6)]Gal(beta1-4)Glc; the saccharides from another animal: alpha3'-galactosyllactose, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc, A-tetrasaccharide, GalNAc(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)[Fuc(alpha1-3)]Glc (A-pentasaccharide), Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Gl c, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)[F uc(alpha1-3)]Glc (difucosylheptasaccharide) and Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)?Gal(alpha1-3) Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)?Gal(beta1-4)Glc (difucosyldecasaccharide). Lactose was present only in small amounts. Some of the milk oligosaccharides of the polar bear had alpha-Gal epitopes similar to some oligosaccharides in milk from the Ezo brown bear and the Japanese black bear. Some milk oligosaccharides had human blood group A antigens as well as B antigens; these were different from the oligosaccharides in Ezo brown and Japanese black bears.  相似文献   

3.
The biotransformation of raspberry ketone and zingerone were individually investigated using cultured cells of Phytolacca americana. In addition to (2S)-4-(4-hydroxyphenyl)-2-butanol (2%), (2S)-4-(3,4-dihydroxyphenyl)-2-butanol (5%), 4-[4-(beta-d-glucopyranosyloxy)phenyl]-2-butanone (19%), 4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (23%), and (2S)-4-(4-hydroxyphenyl)but-2-yl-beta-d-glucopyranoside (20%), two biotransformation products, i.e., 2-hydroxy-4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (12%) and 2-hydroxy-5-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (11%), were isolated from suspension cells after incubation with raspberry ketone for three days. On the other hand, two compounds, i.e., (2S)-4-(4-hydroxy-3-methoxyphenyl)but-2-yl-beta-d-glucopyranoside (17%) and (2S)-2-(beta-d-glucopyranosyloxy)-4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]butane (16%), together with (2S)-4-(4-hydroxy-3-methoxyphenyl)-2-butanol (15%), 4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]-2-butanone (21%), and 4-[(3S)-3-hydroxybutyl]-2-methoxyphenyl-beta-d-glucopyranoside (24%) were obtained upon addition of zingerone. Cultured cells of P. americana can reduce, and regioselectively hydroxylate and glucosylate, these food ingredients to their beta-glycosides.  相似文献   

4.
A sugar autoanalyzer was used on a preparative scale to resolve a gluco-oligosaccharide mixture. In this way the components of the following mixtures were resolved: O-alpha-D-glucopyranosyl-(1-3)-O-[alpha-D-glucopyranosyl-(1-6)]-D-glucose (1), O-alpha-D-glucopyranosyl-(1-6)-O-alpha-D-glucopyranosyl-(1-3)-D-glucose (2) and O-alpha-D-glucopyranosyl-(1-3)-O-alpha-D-glucopyranosyl-(1-6)-D-glucose (3), O-alpha-D-glucopyranosyl-(1-3)-O-alpha-D-glucopyranosyl-(1-4)-D-glucose (4) and O-alpha-D-glucopyranosyl-(1-4)-O-alpha-D-glucopyranosyl-(1-3)-D-glucose (5), and O-alpha-D-glucopyranosyl-(1-2)-O-alpha-D-glucopyranosyl-(1-6)-O-alpha-D-glucopranosyl-(1-6)-O-alpha-D-glucopyranosyl-(1-6)-D-glucose (6) and O-alpha-D-glucopyranosyl-(1-3)--O-alpha-D-glucopyranosyl-(1-6)-O-alpha-D-glucopyranosyl-(1-6)-O-alpha-D-glucopyranosyl-(1-6)-D-glucose (7).  相似文献   

5.
При изучении микробных преврашений у микроорганизмов, расщепляюших молекулC прогестерона различным способом (таблица 1), было установлено, что как лактон (±)-5-оксо-8α-окси-цис1,4,5,8,9,10-гек сагидронафтойной кислоты (I), так и лактон (±)-5,8-диокси-цис-l,4,5,8,9,10-гексаг идронафтойной кислоты (II) превращаются приводимыми штаммами микробов в одинаковыйпродукт трансформации, а именно, в лактон (±)-5-оксо-81-окси-цисΔ2-окт алин-l1-карбоновой кислоты.  相似文献   

6.
Structural characterizations of marsupial milk oligosaccharides have been performed in only three species: the tammar wallaby, the red kangaroo and the koala. To clarify the homology and heterogeneity of milk oligosaccharides among marsupials, 21 oligosaccharides of the milk carbohydrate fraction of the common brushtail possum were characterized in this study. Neutral and acidic oligosaccharides were separated from the carbohydrate fraction of mid-lactation milk and characterized by 1H-nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The structures of the 7 neutral oligosaccharides were Gal(β1-3)Gal(β1-4)Glc (3’-galactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc (3”, 3’-digalactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I), Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (galactosyl lacto-N-novopentaose I), Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-3)Gal(β1-4)Glc (galactosyl lacto-N-novopentaose II). The structures of the 14 acidic oligosaccharides detected were Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Glc (sialyl 3’-galactosyllactose), Gal(β1-3)(O-3-sulfate)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I sulfate a) Gal(β1-3)[Gal(β1-4)(O-3-sulfate)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I sulfate b), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)(?3-O-sulfate)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)[Gal(β1-4)(?3-O-sulfate)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose b), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(?3-O-sulphate)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)(?3-O-sulphate)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)(?3-O-sulphate)GlcNAc(β1-6)]Gal(β1-4)Glc and Gal(β1-3)Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (galactosyl sialyl lacto-N-novopentaose b). No fucosyl oligosaccharides were detected. Galactosyl lacto-N-novopentaose II, lacto-N-novopentaose I sulfate a, lacto-N-novopentaose I sulfate b and galactosyl sialyl lacto-N-novopentaose b are novel oligosaccharides. The results are compared with those of previous studies on marsupial milk oligosaccharides.  相似文献   

7.
In the milk of marsupials, oligosaccharides usually predominate over lactose during early to mid lactation. Studies have shown that tammar wallaby milk contains a major series of neutral galactosyllactose oligosaccharides ranging in size from tri- to at least octasaccharides, as well as β(1-6) linked N-acetylglucosamine-containing oligosaccharides as a minor series. In this study, acidic oligosaccharides were purified from red kangaroo milk and characterized by (1)H-nuclear magnetic resonance spectrometry and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, to be as follows: Neu5Ac(α2-3)Gal(β1-4)Glc (3'-SL), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Glc (sialyl 3'-galactosyllactose), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose b), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc. These acidic oligosaccharides were shown to be sialylated or sulfated in the non-reducing ends to the major linear and the minor branched series of neutral oligosaccharides of tammar wallaby milk.  相似文献   

8.
Two trisaccharides, three tetrasaccharides, two pentasaccharides, one hexasaccharide, one heptasaccharide, one octasaccharide and one decasaccharide were isolated from polar bear milk samples by chloroform/methanol extraction, gel filtration, ion exchange chromatography and preparative thin-layer chromatography. The oligosaccharides were characterized by 1H-NMR as follows: the saccharides from one animal: Gal(α1-3)Gal(β1-4)Glc (α3′-galactosyllactose), Fuc(α1-2)Gal(β1-4)Glc (2′-fucosyllactose), Gal(α1-3)[Fuc(α1-2)]Gal(β1-4)Glc (B-tetrasaccharide), GalNAc(α1-3)[Fuc(α1-2)]Gal(β1-4)Glc (A-tetrasaccharide), Gal(α1-3)Gal(β1-4)GlcNAc(β1-3)Gal(β1-4)Glc, Gal(α1-3)[Fuc(α1-2)]Gal(β1-4)GlcNAc(β1-3)Gal(β1-4)Glc, Gal(α1-3)Gal(β1-4)GlcNAc(β1-3)[Gal(α1-3)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc; the saccharides from another animal: α3′-galactosyllactose, Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]Glc, A-tetrasaccharide, GalNAc(α1-3)[Fuc(α1-2)]Gal(β1-4)[Fuc(α1-3)]Glc (A-pentasaccharide), Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-3)Gal(β1-4)Glc, Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-3)Gal(β1-4)[Fuc(α1-3)]Glc (difucosylheptasaccharide) and Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-3){Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)}Gal(β1-4)Glc (difucosyldecasaccharide). Lactose was present only in small amounts. Some of the milk oligosaccharides of the polar bear had α-Gal epitopes similar to some oligosaccharides in milk from the Ezo brown bear and the Japanese black bear. Some milk oligosaccharides had human blood group A antigens as well as B antigens; these were different from the oligosaccharides in Ezo brown and Japanese black bears.  相似文献   

9.
Hydrochloric acid treatment of methyl 3-(4-isobutylphenyl)-3-methylglycidate and methyl 2-hydroxy-3-(4-isobutylphenyl)-3-butenoate, a rearrangement product of the former, in acetic acid gave 3-(4-isobutylphenyl)-3-methylpyruvic acid and 2-(4-isobutylphenyl)-pro-panal. The same treatment of 2-hydroxy-3-(4-isobutylphenyl)-3-butenoic acid gave 2-(4-isobutylphenyl)-propanal. Both 3-(4-isobutylphenyl)-3-methylpyruvic acid and 2-(4-iso-butylphenyl)-propanal were oxidized to 2-(4-isobutylphenyl)-propionic acid.  相似文献   

10.
Racemic 2-aryl-2-methoxypropionic acids were enantioresolved by the use of (S)-(-)-phenylalaninol 4. For instance, racemic 2-methoxy-2-phenylpropionic acid (+/-)-7 was condensed with phenylalaninol (S)-(-)-4 yielding a diastereomeric mixture of amides, which was easily separated by HPLC on silica gel affording the first-eluted amide (-)-13a and the second-eluted amide (+)-13b: alpha = 3.19, Rs = 3.49. The absolute configuration of amide (-)-13a was determined to be (R;S) by X-ray crystallography by reference to the S configuration of the phenylalaninol moiety. Amide (R;S)-(-)-13a was converted to oxazoline (R;S)-(-)-14a, from which enantiopure 2-methoxy-2-phenylpropionic acid (R)-(-)-7 was recovered. Other 2-aryl-2-methoxypropionic acids, (R)-(-)-8, (R)-(-)-9, (R)-(+)-10, (R)-(-)-11, and (R)-(-)-12, were similarly prepared in enantiopure forms with the use of phenylalaninol (S)-(-)-4, and their absolute configurations were clearly determined by X-ray crystallography or by chemical correlation.  相似文献   

11.
Two trisaccharides, two tetrasaccharides, one penta-, one hexa-, two hepta-, one deca- and two undeca-saccharides were isolated from several Japanese black bear milk samples by chloroform/methanol extraction, gel filtration and preparative thin-layer chromatography. The oligosaccharides were characterized by 1H-NMR as follows: Gal(alpha 1-3)Gal(beta 1-4)Glc (alpha 3'-galactosyllactose), Fuc(alpha 1-2)Gal(beta 1-4)Glc (2'-fucosyllactose), Gal(alpha 1-3)(Fuc(alpha 1-2))Gal(beta 1-4)Glc (B-tetrasaccharide), Gal(alpha 1-3)Gal(beta 1-4)(Fuc(alpha 1-3))Glc, Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]Glc (B-pentasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4)Glc (monofucosylhexasaccharide), Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4)Glc (difucosylheptasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]Glc (difucosylheptasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)[Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-6)]Gal(beta 1-4)Glc (difucosyldecasaccharide), Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)[Gal(alpha 1-3) Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-6)]Gal(beta 1-4)Glc (trifucosylundecasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)[Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-6)]Gal(beta 1-4)Glc (trifucosylundecasaccharide). Lactose was present only in trace amounts. B-pentasaccharide was a dominant saccharide in early lactation milk, while alpha 3'-galactosyllactose was dominant in milk, later. The milk oligosaccharides of the Japanese black bear were compared with those of the Ezo brown bear.  相似文献   

12.
Previous structural characterizations of marsupial milk oligosaccharides had been performed in only two macropod species, the tammar wallaby and the red kangaroo. To clarify the homology and heterogeneity of milk oligosaccharides among marsupial species, which could provide information on their evolution, the oligosaccharides of the koala milk carbohydrate fraction were characterized in this study. Neutral and acidic oligosaccharides were separated from the carbohydrate fraction of milk of the koala, a non-macropod marsupial, and characterized by 1H-nuclear magnetic resonance spectroscopy. The structures of the neutral saccharides were found to be Gal(β1-4)Glc (lactose), Gal(β1-3)Gal(β1-4)Glc (3′-galactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc (3′,3″-digalactosyllactose), Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I) and Gal(β1-3){Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)}Gal(β1-4)Glc (fucosyl lacto-N-novopentaose I), while those of the acidic saccharides were Neu5Ac(α2-3)Gal(β1-4)Glc (3′-SL), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Gal (sialyl 3′-galactosyllactose), Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose b), Gal(β1-3)[Neu5Ac(α2-3)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose c), and Neu5Ac(α2-3)Gal(β1-3){Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)}Gal(β1-4)Glc (fucosyl sialyl lacto-N-novopentaose a). The neutral oligosaccharides, other than fucosyl lacto-N-novopentaose I, a novel hexasaccharide, had been found in milk of the tammar wallaby, a macropod marsupial, while the acidic oligosaccharides, other than fucosyl sialyl lacto-N-novopentaose a had been identified in milk carbohydrate of the red kangaroo. The presence of fucosyl oligosaccharides is a significant feature of koala milk, in which it differs from milk of the tammar wallaby and the red kangaroo.  相似文献   

13.
The oligosaccharides present in the milk of an African elephant (Loxodonta africana africana), collected 4 days post partum, were separated by size exclusion-, anion exchange- and high-performance liquid chromatography (HPLC) before characterisation by (1)H NMR spectroscopy. Neutral and acidic oligosaccharides were identified. Neutral oligosaccharides characterised were isoglobotriose, Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc, Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc and a novel oligosaccharide that has not been reported in the milk or colostrum of any other mammal: Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc. Acidic oligosaccharides that are also found in the milk of Asian elephant were Neu5Ac(alpha2-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-6)Gal(beta1-4)Glc, Neu5Ac(alpha2-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc and Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3){Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)}Gal(beta1-4)Glc, while Neu5Gc(alpha2-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)[Gal(beta1-4)GlcNAc(beta1-6)]Gal(beta1-4)Glc and Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3){Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)}Gal(beta1-4)Glc have not been found in Asian elephant milk. The oligosaccharides characterised contained both alpha(2-3)- and alpha(2-6)-linked Neu5Ac residues. They also contain only the type II chain, as found in most non-human, eutherian mammals.  相似文献   

14.
The distribution of ABO, Rh and MN blood groups among 6450 persons of six main nationalities in Karaganda is found to be the following (in percent); O blood group-Ukrainians (34.04+/-1.5), Germans (35.46+/-1.5), Kazakhs(34.62+/-1.6), Tatars (35.9+/-2.2), Russians (37.01+/-1.5), Byelorussians (40.36+/-2.4); A blood group--Kazakhs (27.47+/-1.5), Tatars (32.57+/-2.1), Russians (32.66+/-1.5), Byelorussians (37.23+/-2.4), Ukrainians (37.70+/-1.5), Germans (46.32+/-1.5); B blood group--Germans (13.37+/-1.1), Byelorussians (16.55+/-1.8), Ukrainians (19.30+/-1.3), Russians (23.11+/-1.3), Tatars (24.22+/-0.2), Kazakhs (28.33+/-1.5); AB blood group--Germans (4.85+/-0.7), Byelorussians (5.86+/-1.2), Tatars (7.30+/-1.2), Russians (7.22+/-0.8), Ukrainians (8.96+/-0.9). Reliable differences in Rh system were discovered only in Kazakhs and Tatars, among persons of different nationalities.  相似文献   

15.
NADPH oxidases (NOX) are the major source of reactive oxygen species (ROS) in the vasculature and contribute to the control of renal perfusion. The role of NOX2 in the regulation of blood pressure and afferent arteriole responsiveness was investigated in NOX2(-/-) and wild-type mice. Arteriole constrictions to ANG II (10(-14)-10(-6) mol/l) were weaker in NOX2(-/-) compared with wild types. N(omega)-nitro-l-arginine methyl ester (l-NAME; 10(-4) mol/l) treatment reduced basal diameters significantly more in NOX2(-/-) (-18%) than in wild types (-6%) and augmented ANG II responses. Adenosine (10(-11)-10(-4) mol/l) constricted arterioles of wild types but not of NOX2(-/-). However, simultaneous inhibition of adenosine type-2 receptors induced vasoconstriction, which was stronger in NOX2(-/-). Adenosine (10(-8) mol/l) enhanced the ANG II response in wild type, but not in NOX2(-/-). This sensitizing effect by adenosine was abolished by apocynin. Chronic ANG II pretreatment (14 days) did not change the ANG II responses in NOX2(-/-), but strengthened the response in wild types. ANG II pretreatment augmented the l-NAME response in NOX2(-/-) (-33%), but not in wild types. Simultaneous application of l-NAME and ANG II caused a stronger constriction in the NOX2(-/-) (-64%) than in wild types (-46%). Basal blood pressures were similar in both genotypes, however, chronic ANG II infusion elevated blood pressure to a greater extent in wild-type (15 +/- 1%) than in NOX2(-/-) (8 +/- 1%) mice. In conclusion, NOX2 plays an important role in the control of afferent arteriole tone and is involved in the contractile responses to ANG II and/or adenosine. NOX2 can be activated by elevated ANG II and may play an important role in ANG II-induced hypertension. NOX2-derived ROS scavenges nitric oxide, causing subsequent nitric oxide-deficiency.  相似文献   

16.
New side chain-modified iodothyronines have been synthesized. They include: 1-[4-(4-hydroxyphenoxy)-3,5-diiodophenyl]-1,2-ethanediol (T2EG); alpha-hydroxy-4-(4-hydroxyphenoxy)-3,5-diiodobenzeneacetic acid (T2HAA) and their 4-methyl ether derivatives (MT2EG, MT2HAA); 1-[4-(4-hydroxyphenoxy)-3,5-diiodophenyl]-2-aminoethanol (T2EA); 1-[4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl]-1,2-ethaned iol (T3EG); 1-[4-(4-hydroxy-3-iodophenoxy)-3,5-diiodophenyl]-2-aminoetha nol (T3EA); and alpha-hydroxy-4-(3-iodo-4-hydroxyphenoxy)-3,5-diiodobenzeneacet ic acid (T3HAA). These model compounds are being used to study thyroid hormone metabolism and to determine structure-activity relationships of iododiphenylether derivatives.  相似文献   

17.
Seven glutathione-S-transferase (GST) isozymes were purified from liver cytosol of intact male Wistar rats: 1-1(A), 1-1(B), 1-2, 2-2, 3-3, 3-4, 4-4. Treatment of rats with butylated hydroxytoluene (BHT) led to the induction of isozymes GST 1-1(A), 1-1(B) (2-fold), 3-3 (3.5-fold) as well as to the appearance of two new isozymes--1-3 and 4-4(A). Phenobarbital (PB) induced isozymes GST 1-1(A), 1-1(B) (2-fold) and 3-3 (1.5-fold). BHT and PB caused an increase in the specific activity of isozymes 1-1(A), 1-1(B), 3-3, 3-4 towards 1-chloro-2.4-dinitrobenzene and 1.2-dichloro-4-nitrobenzene. 3-Methylcholanthrene (MC) induced isozymes 1-2 (1.5-fold), 2-2 (2-fold) and 4-4 (3-fold). A conclusion was drawn that BHT and PB induced the GST subunits 1 and 3, whereas MC--subunits 2 and 4.  相似文献   

18.
Mechanism of reaction of myeloperoxidase with nitrite   总被引:10,自引:0,他引:10  
Myeloperoxidase (MPO) is a major neutrophil protein and may be involved in the nitration of tyrosine residues observed in a wide range of inflammatory diseases that involve neutrophils and macrophage activation. In order to clarify if nitrite could be a physiological substrate of myeloperoxidase, we investigated the reactions of the ferric enzyme and its redox intermediates, compound I and compound II, with nitrite under pre-steady state conditions by using sequential mixing stopped-flow analysis in the pH range 4-8. At 15 degrees C the rate of formation of the low spin MPO-nitrite complex is (2.5 +/- 0.2) x 10(4) m(-1) s(-1) at pH 7 and (2.2 +/- 0.7) x 10(6) m(-1) s(-1) at pH 5. The dissociation constant of nitrite bound to the native enzyme is 2.3 +/- 0.1 mm at pH 7 and 31.3 +/- 0.5 micrometer at pH 5. Nitrite is oxidized by two one-electron steps in the MPO peroxidase cycle. The second-order rate constant of reduction of compound I to compound II at 15 degrees C is (2.0 +/- 0.2) x 10(6) m(-1) s(-1) at pH 7 and (1.1 +/- 0.2) x 10(7) m(-1) s(-1) at pH 5. The rate constant of reduction of compound II to the ferric native enzyme at 15 degrees C is (5.5 +/- 0.1) x 10(2) m(-1) s(-1) at pH 7 and (8.9 +/- 1.6) x 10(4) m(-1) s(-1) at pH 5. pH dependence studies suggest that both complex formation between the ferric enzyme and nitrite and nitrite oxidation by compounds I and II are controlled by a residue with a pK(a) of (4.3 +/- 0.3). Protonation of this group (which is most likely the distal histidine) is necessary for optimum nitrite binding and oxidation.  相似文献   

19.
The in vitro Ca(2+) regulation of the actomyosin Mg(2+)-ATPase at physiological ratios of actin, tropomyosin, and troponin occurs only in the presence of troponin T. We have previously demonstrated that a polypeptide corresponding to the first 191 amino acids of troponin T (TnT-(1-191)) activates the actomyosin Mg(2+)-ATPase in the presence of tropomyosin. In order to further characterize this activation domain, we constructed troponin T fragments corresponding to residues 1-157 (TnT-(1-157)), 1-76 (TnT-(1-76)), 77-157 (TnT-(77-157)), 77-191 (TnT-(77-191)), and 158-191 (TnT-(158-191)). Assays using these fragments demonstrated the following: (a) residues 1-76 do not bind to tropomyosin or actin; (b) residues 158-191 bind to actin cooperatively but not to tropomyosin; (c) the sequence 77-157 is necessary for troponin interaction with residue 263 of tropomyosin; (d) TnT-(77-191) on its own activates the actomyosin ATPase activity as described previously for TnT-(1-191). TnT-(1-157), TnT-(1-76), TnT-(77-157), TnT-(158-191), and combinations of TnT-(158-191) with TnT-(1-157) or TnT-(77-157) showed no effect on the ATPase activity. We conclude that the activation of actomyosin ATPase activity is mediated by a direct interaction between amino acids 77 and 191 of troponin T, tropomyosin, and actin.  相似文献   

20.
Effects of the anthelmintics, pyrantel and levamisole, on egg development of Angiostrongylus costaricensis were studied in vitro. After 7 days, about 80% of eggs developed to first-stage larvae in Ham's F-12 medium with 10% foetal calf serum under 5% CO2. Significant inhibition of development was caused by pyrantel (10(-9) - 10(-8) g ml(-1)) and levamisole (10(-9) - 10(-8) g ml(-1)) (Mann-Whitney U-test; ), and none of the eggs developed to first-stage larvae in higher concentrations of these anthelmintics (10(-7) g ml(-1)). Furthermore, incubation with these drugs at 10(-8) g ml(-1) for at least 3 h or at 10(-4) g ml(-1) for 1 h caused irreversible effects on egg development.  相似文献   

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