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1.
S Kaya  K Yokoyama  Y Araki    E Ito 《Journal of bacteriology》1984,158(3):990-996
The structure of teichoic acid-glycopeptide complexes isolated from lysozyme digests of cell walls of Bacillus subtilis (four strains) and Bacillus licheniformis (one strain) was studied to obtain information on the structural relationship between glycerol teichoic acids and their linkage saccharides. Each preparation of the complexes contained equimolar amounts of muramic acid 6-phosphate and mannosamine in addition to glycopeptide components and glycerol teichoic acid components characteristic of the strain. Upon treatment with 47% hydrogen fluoride, these preparations gave, in common, a hexosamine-containing disaccharide, which was identified as N- acetylmannosaminyl (1----4) N-acetylglucosamine, along with large amounts of glycosylglycerols presumed to be the dephosphorylated repeating units of teichoic acid chains. The glycosylglycerol obtained from each bacterial strain was identified as follows: B. subtilis AHU 1392, glucosyl alpha (1----2)glycerol; B. subtilis AHU 1235, glucosyl beta(1----2) glycerol; B. subtilis AHU 1035 and AHU 1037, glucosyl alpha (1----6)galactosyl alpha (1----1 or 3)glycerol; B. licheniformis AHU 1371, galactosyl alpha (1----2)glycerol. By means of Smith degradation, the galactose residues in the teichoic acid-glycopeptide complexes from B. subtilis AHU 1035 and AHU 1037 and B. licheniformis AHU 1371 were shown to be involved in the backbone chains of the teichoic acid moieties. Thus, the glycerol teichoic acids in the cell walls of five bacterial strains seem to be joined to peptidoglycan through a common linkage disaccharide, N- acetylmannosaminyl (1----4)N-acetylglucosamine, irrespective of the structural diversity in the glycosidic branches and backbone chains.  相似文献   

2.
N Kojima  Y Araki    E Ito 《Journal of bacteriology》1985,161(1):299-306
The structure of the linkage regions between ribitol teichoic acids and peptidoglycan in the cell walls of Staphylococcus aureus H and 209P and Bacillus subtilis W23 and AHU 1390 was studied. Teichoic acid-linked saccharide preparations obtained from the cell walls by heating at pH 2.5 contained mannosamine and glycerol in small amounts. On mild alkali treatment, each teichoic acid-linked saccharide preparation was split into a disaccharide identified as N-acetylmannosaminyl beta(1----4)N-acetylglucosamine and the ribitol teichoic acid moiety that contained glycerol residues. The Smith degradation of reduced samples of the teichoic acid-linked saccharide preparations from S. aureus and B. subtilis gave fragments characterized as 1,2-ethylenediol phosphate-(glycerolphosphate)3-N-acetylmannosaminyl beta(1----4)N- -acetylxylosaminitol and 1,2-ethylenediolphosphate-(glycerol phosphate)2-N-acetylmannosaminyl beta(1----4)N-acetylxylosaminitol, respectively. The binding of the disaccharide unit to peptidoglycan was confirmed by the analysis of linkage-unit-bound glycopeptides obtained from NaIO4 oxidation of teichoic acid-glycopeptide complexes. Mild alkali treatment of the linkage-unit-bound glycopeptides yielded disaccharide-linked glycopeptides, which gave the disaccharide and phosphorylated glycopeptides on mild acid treatment. Thus, it is concluded that the ribitol teichoic acid chains in the cell walls of the strains of S. aureus and B. subtilis are linked to peptidoglycan through linkage units, (glycerol phosphate)3-N-acetylmannosaminyl beta(1----4)N-acetylglucosamine and (glycerol phosphate)2-N-acetylmannosaminyl beta(1----4)N-acetylglucosamine, respectively.  相似文献   

3.
The minor teichoic acid linked to glycopeptide was isolated from lysozyme digests of Bacillus coagulans AHU 1631 cell walls, and the structure of the teichoic acid moiety and its junction with the peptidoglycan were studied. Hydrolysis of the teichoic-acid--glycopeptide complex with hydrogen fluoride gave a nonreducing oligosaccharide composed of glucose, galactose and glycerol in a molar ratio of 3:1:1 which was presumed to be dephosphorylated repeating units of the polymer chain. From the results of structural analysis involving NaIO4 oxidation, methylation and acetolysis, the above fragment was characterized as glucosyl(beta 1----3)glucosyl(beta 1----6)galactosyl(beta 1----6)glucosyl(alpha 1----1/3)glycerol. In addition, the Smith degradation of the complex yielded a phosphorus-containing fragment identified as glycerol-P-6-glucosyl(beta 1----1/3)glycerol. These results led to the most likely structure for the repeating units of the teichoic acid, -6[glucosyl(beta 1----3)]glucosyl(beta 1----6)galactosyl(beta 1----6)glucosyl(alpha 1----1/3)glycerol-P-. The minor teichoic acid, just like the major teichoic acid bound to the linkage unit, was released by heating the cell walls at pH 2.5. The mild alkaline hydrolysis of the minor teichoic acid after reduction with NaB3H4 gave labeled saccharides characterized as glucosyl(beta 1----6)galactitol and glucosyl(beta 1----3)glucosyl(beta 1----6)galactitol, together with a large amount of the unlabeled repeating units of the teichoic acid chain. Thus, the minor teichoic acid chain is believed to be directly linked to peptidoglycan at the galactose residue of the terminal repeating unit without a special linkage sugar unit.  相似文献   

4.
The HF treatment of teichoic acid-glycopeptide complexes isolated from lysozyme digests of Bacillus coagulans AHU 1366 cell walls gave a disaccharide, glucosyl beta (1 leads to 4)N-acetylglucosamine, along with dephosphorylated repeating units of the teichoic acid chain, galactosyl alpha (1 leads to 2) glycerol. Mild alkali treatment of the complexes yielded the disaccharide linked to glycopeptide, whereas direct heating of the cell walls at pH 2.5 yielded the same disaccharide linked to teichoic acid. The Smith degradation of the complexes revealed that the galactose residue is a component of backbone chain. Thus it is concluded that this disaccharide is involved in the linkage region between poly(galactosylglycerol phosphate) and peptidoglycan in cell walls. Membrane-catalyzed synthesis of this disaccharide on a lipid followed by transfer of glycerol phosphate from CDP-glycerol to the disaccharide-linked lipid in the absence or in the presence of UDP-galactose also supports this conclusion.  相似文献   

5.
D-[alpha-14C]]glucosyl phosphorylpolyprenol ([ 14C]Glc-P-prenol) was formed from UDP-D-[14C]glucose in each of the membrane systems obtained from Bacillus coagulans AHU 1631 and AHU 1634 and two Bacillus megaterium strains. Membranes of these B. coagulans strains, which possess beta-D-glucosyl branches on the repeating units in their major cell wall teichoic acids, were shown to catalyze the transfer of the glucose residue from [14C]Glc-P-prenol to endogenous polymer. On the other hand, membranes of B. coagulans AHU 1366, which has no glucose substituents in the cell wall teichoic acid, exhibited neither [14C]Glc-P-prenol synthetase activity nor the activity of transferring glucose from [14C]Glc-P-prenol to endogenous acceptor. The enzyme which catalyzes the polymer glycosylation in the former two B. coagulans strains was most active at pH 5.5 and in the presence of the Mg2+ ion. The apparent Km for [14C]Glc-P-prenol was 0.6 microM. Hydrogen fluoride hydrolysis of the [14C]glucose-linked polymer product yielded a major fragment identical to D-galactosyl-alpha(1----2)(D-glucosyl-beta(1----1/3)) glycerol, the dephosphorylated repeating unit in the major cell wall teichoic acids of these B. coagulans strains. This result, together with the behavior of the radioactive polymer in chromatography on Sepharose CL-6B, DEAE-Sephacel, and Octyl-Sepharose CL-4B, led to the conclusion that [14C]Glc-P-prenol serves as an intermediate in the formation of beta-D-glucosyl branches on the polymer chains of cell wall teichoic acids in B. coagulans.  相似文献   

6.
Structural studies were carried out on the teichoic acids in cell walls of Listeria monocytogenes serotypes 3a, 4b, 4f, 6, and 7. The structure of the dephosphorylated repeating units, obtained by treatment with 46% hydrogen fluoride or alkaline hydrolysis, was examined by methylation analysis, acetolysis, and 1H-NMR spectroscopy. The results of Smith degradation of the teichoic acids and 13C-NMR spectroscopy led to the following most likely structures of the repeating units of the teichoic acids:----1-[N-acetylglucosaminyl(alpha 1----4)]ribitol-5-phosphate----for serotype 3a,----4-[galactosyl(alpha 1----6)][glucosyl(beta 1----3)]N -acetylglucosaminyl(beta 1----2)ribitol-5-phosphate----for serotype 4b,----4-[galactosyl(alpha 1----6)][N -acetylglucosaminyl(alpha 1----3)]N-acetylglucosaminyl(beta 1----2)ribitol -5-phosphate----for serotype 4f,----4-N-acetylglucosaminyl(beta 1----4)ribitol -5-phosphate----for serotype 6, and----1-ribitol-5-phosphate----for serotype 7. About 40% of the repeating units of the teichoic acid from serotype 4f were not substituted at C-3 of beta-N-acetylglucosaminyl residues.  相似文献   

7.
The structure of the linkage unit between ribitol teichoic acid and peptidoglycan in the cell walls of Listeria monocytogenes EGD was studied. A teichoic-acid--glycopeptide preparation isolated from lysozyme digests of the cell walls of this strain contained mannosamine, glycerol, glucose and muramic acid 6-phosphate in an approximate molar ratio of 1:1:2:1, together with large amounts of glucosamine and other components of teichoic acid and glycopeptides. A teichoic-acid-linked sugar preparation, obtained by heating the cell walls at pH 2.5, also contained glucosamine, mannosamine, glycerol and glucose in an approximate molar ratio of 25:1:1:2. Part of the glucosamine residues were shown to be involved in the linkage unit. Thus, on mild alkaline hydrolysis, the teichoic-acid-linked sugar preparation gave a disaccharide characterized as N-acetylmannosaminyl(beta 1----4)-N-acetylglucosamine [ManNAc(beta 1----4)GlcNAc] in addition to the ribitol teichoic acid moiety, whereas the teichoic-acid - glycopeptide was separated into disaccharide-linked glycopeptide and the ribitol teichoic acid moiety by the same procedure. Furthermore, Smith degradation of the cell walls gave a characteristic fragment, EtO2-P-Glc(beta 1----3)Glc(beta 1----1/3)Gro-P-ManNAc(beta 1----4)GlcNAc (where EtO2 = 1,2-ethylenediol and Gro = glycerol). The results lead to the conclusion that in the cell walls of this organism, the ribitol teichoic acid chain is linked to peptidoglycan through a novel linkage unit, Glc(beta 1----3)Glc(beta 1----1/3)Gro-P-(3/4)ManNAc-(beta 1----4)GlcNAc.  相似文献   

8.
Structural studies were carried out on two kinds of teichuronic acid-glycopeptide complexes (designated as TU-GP-I and TU-GP-II) isolated from lysozyme digest of N-acetylated cell walls of Bacillus megaterium AHU 1375 by ion-exchange chromatography and gel chromatography. TU-GP-I, accounting for about 25% of the cell walls, contained N-acetylmannosaminuronic acid, N-acetylglucosamine, glucose, galactose, glycerol, and phosphorus in an approximate molar ratio of 1:1:2:1:0.5:0.5, together with small amounts of glycopeptide components. TU-GP-II, accounting for about 9% of the cell walls, contained glucuronic acid, glucose, and fucose in a molar ratio of about 2:1.5:1, together with small amounts of glycopeptide components. The results of analyses involving Smith degradation, chromium oxidation, methylation, acetolysis, and H-NMR measurement led to the conclusion that the polysaccharide chain of TU-GP-I comprised repeating units,----6) Glc(alpha 1----3)-ManNAcUA(beta 1----4)[Gal(alpha 1----3)][Glc(beta 1----6)]GlcNAc(beta 1----. About half of the repeating units were substituted by glycerophosphoryl residues at C-6 of the beta-glucosyl residues linked to the N-acetylglucosamine residues. By means of a similar procedure, the polysaccharide chain of TU-GP-II was shown to comprise repeating units,----4)GlcUA(alpha 1----3)GlcUA(alpha 1----3)Glc(alpha 1----3)Fuc(alpha 1----, of which about half were substituted by alpha-glucosyl residues at C-3 of the 4-substituted glucuronosyl residues.  相似文献   

9.
The primary structure of teichuronic acid in Bacillus subtilis AHU 1031   总被引:3,自引:0,他引:3  
Structural studies were carried out on the acidic polysaccharide fraction obtained from lysozyme digest of the cell walls of Bacillus subtilis AHU 1031. The polysaccharide fraction contained N- acetylmannosaminuronic acid ( ManNAcA ), N-acetylglucosamine (GlcNAc), glucose, glycerol and phosphorus in a molar ratio of 2:2:4:1:1, together with glycopeptide components. The results of analyses involving Smith degradation, chromium trioxide oxidation, methylation and proton magnetic resonance spectroscopy led to the conclusion that the backbone chain of the polysaccharide has the repeating unit----6)Glc(alpha 1----3/4) ManNAcA (beta 1----4)GlcNAc(beta 1----. About 50% of the N-acetylglucosamine residues in the backbone chain seem to be substituted at C-3 by the glycosidic branches, glycerol phospho-6-glucose, while the other half seem to be substituted by glucose.  相似文献   

10.
New neutral oligosaccharides from cow colostrum kappa-casein were identified and characterized by 500-MHz 1H-NMR spectroscopy. Their structures are Gal beta(1----3)GalNAc-ol, Gal beta(1----3)[GlcNAc beta(1----6)]GalNAc-ol, Gal beta(1----3)[Gal beta(1----4)GlcNAc beta(1----6)]GalNAc-ol, Gal beta(1----3)[Fuc alpha(1----3)[Gal beta(1----4)]GlcNAc beta(1----6)]GalNAc-ol. The tetrasaccharide and the cow colostrum kappa-caseinoglycopeptide which contains this oligosaccharide inhibit the hemagglutination of blood group I human erythrocytes. In cow mature milk only the disaccharide is characterized. The variability of these neutral oligosaccharides in cow kappa-casein as a function of time after calving is studied.  相似文献   

11.
Biosynthesis of poly(galactosylglycerol phosphate) in Bacillus coagulans   总被引:4,自引:0,他引:4  
The pathway for the de novo synthesis of a teichoic acid, poly(galactosylglycerol phosphate), in Bacillus coagulans AHU 1366 was studied by means of characterization and stepwise conversion of lipid-linked intermediates. Incubation of membranes with UDP-N-acetylglucosamine and UDP-glucose yielded a disaccharide-linked polyprenylpyrophosphate, whose sugar moiety was characterized as glucosyl(beta 1----4)N-acetylglucosamine (Glc-GlcNAc). By incubation with membranes and CDP-glycerol, Glc-GlcNAc-PP-prenol was converted to a series of glycolipids characterized as (Gro-P)1-6-Glc-GlcNAc-PP-prenol (Gro = glycerol). Glc-[14C]GlcNAc-PP-prenol was converted to polymer by incubation with membranes, CDP-glycerol and UDP-galactose. Smith degradation of the polymer gave two radioactive fragments corresponding to (Gro-P)3-Glc-GlcNAc and (Gro-P)4-Glc-GlcNAc. These results, together with data on gel chromatography of radioactive polymer synthesized from UDP-[3H]galactose, CDP-glycerol and Glc-[14C]GlcNAc-PP-prenol, led to the conclusion that in this strain poly(galactosylglycerol phosphate) is probably synthesized through the following pathway: GlcNAc-PP-prenol----Glc-GlcNAc-PP-prenol----(Gro-P)3-4 -Glc-GlcNAc-PP-prenol----(Gro-P-Gal)n- (Gro-P)3-4-Glc-GlcNAc-PP-prenol----(Gro-P-Gal)n- (Gro-P)3-4-Glc-GlcNAc-P-peptidoglycan complex.  相似文献   

12.
Preparations of membrane plus wall derived from Bacillus subtilis W23 were used to study the in vitro synthesis of peptidoglycan and teichoic acid and their linkage to the preexisting cell wall. The teichoic acid synthesis showed an ordered requirement for the incorporation of N-acetylglucosamine from uridine 5'-diphosphate (UDP)-N-acetylglucosamine followed by addition of glycerol phosphate from cytidine 5'-diphosphate (CDP)-glycerol and finally by addition of ribitol phosphate from CDP-ribitol. UDP-N-acetylglucosamine was not only required for the synthesis of the teichoic acid, but N-acetylglucosamine residues formed an integral part of the linkage unit attaching polyribitol phosphate to the cell wall. Synthesis of the teichoic acid was exquisitely sensitive to the antibiotic tunicamycin, and this was shown to be due to the inhibition of incorporation of N-acetylglucosamine units from UDP-N-acetylglucosamine.  相似文献   

13.
E Yoon  R A Laine 《Glycobiology》1992,2(2):161-168
Development of tandem mass spectral methods for direct linkage determination in oligosaccharides requires sets of trisaccharides differing only in one structural parameter. In this case, we chose the position of linkage to the reducing-end hexose. These sets of compounds would also be useful for the development of high-resolution separation techniques geared to resolve linkage types. Conventional organic synthesis of such a set could take as long as 2-5 months for each member of the set. Each trisaccharide would require 10-20 steps of synthesis. Instead, we utilized low pH to induce a loose acceptor specificity for bovine milk galactosyltransferase (lactose synthase: EC 2.4.1.22) and by this method, within 2 weeks, generated four novel oligosaccharides for NMR and mass spectral studies. The disaccharides cellobiose (beta 1----4), laminaribiose (beta 1----3), gentiobiose (beta 1----6) and maltose (alpha 1----4) acted as acceptors for EC 2.4.1.22 under these conditions. The beta 1----2-linked disaccharide, sophorose, was not commercially available and is not included in this study. The alpha-linked disaccharides were also examined, but except for the alpha 1----4 disaccharide maltose, were very poor acceptors under a variety of conditions. From these four acceptors, the following four novel trisaccharides were synthesized in micromole amounts, suitable for studies of linkage position using low-energy collision-induced-dissociation tandem mass spectrometry (FAB-MS-CID-MS), and for NMR: Galp(beta 1----4)Glcp(beta 1----3)-Glc, Galp(beta 1----4)Glcp(beta 1----4)Glc, Galp(beta 1----4)Glcp(beta 1----6)-Glc and Galp(beta 1----4)Glcp(alpha 1----4)Glc.  相似文献   

14.
The stepwise formation and characterization of linkage unit intermediates and their functions in ribitol teichoic acid biosynthesis were studied with membranes obtained from Staphylococcus aureus H and Bacillus subtilis W23. The formation of labeled polymer from CDP-[14C]ribitol and CDP-glycerol in each membrane system was markedly stimulated by the addition of N-acetylmannosaminyl(beta 1----4)N-acetylglucosamine (ManNAc-GlcNAc) linked to pyrophosphorylyisoprenol. Whereas incubation of S. aureus membranes with CDP-glycerol and ManNAc-[14C]GlcNAc-PP-prenol led to synthesis of (glycerol phosphate) 1-3-ManNAc-[14C]GlcNAc-PP-prenol, incubation of B. subtilis membranes with the same substrates yielded (glycerol phosphate)1-2-ManNAc-[14C]GlcNAc-PP-prenol. In S. aureus membranes, (glycerol phosphate)2-ManNAc-[14C]GlcNAc-PP-prenol as well as (glycerol phosphate)3-ManNAc-[14C]GlcNAc-PP-prenol served as an acceptor for ribitol phosphate units, but (glycerol phosphate)-ManNAc-[14C]GlcNAc-PP-prenol did not. In B. subtilis W23 membranes, (glycerol phosphate)-ManNAc-[14C]GlcNAc-PP-prenol served as a better acceptor for ribitol phosphate units than (glycerol phosphate)2-ManNAc-[14C]GlcNAc-PP-prenol. In this membrane system (ribitol phosphate)-(glycerol phosphate)-ManNAc-[14C]GlcNAc-PP-prenol was formed from ManNAc-[14C]GlcNAc-PP-prenol, CDP-glycerol and CDP-ribitol. The results indicate that (glycerol phosphate)1-3-ManNAc-GlcNAc-PP-prenol and (glycerol phosphate)1-2-ManNac-GlcNAc-PP-prenol are involved in the pathway for the synthesis of wall ribitol teichoic acids in S. aureus H and B. subtilis W23 respectively.  相似文献   

15.
The structure of sialylated carbohydrate units of bronchial mucins obtained from cystic fibrosis patients was investigated by 500-MHz 1H NMR spectroscopy in conjunction with sugar analysis. After subjecting the mucins to alkaline borohydride degradation, sialylated oligosaccharide-alditols were isolated by anion-exchange chromatography and fractionated by high performance liquid chromatography. Five compounds could be obtained in a rather pure state; their structures were established as the following: A-1, NeuAc alpha(2----3)Gal beta(1----4) [Fuc alpha(1----3)]GlcNAc beta(1----3)Gal-NAc-ol; A-2, NeuAc alpha(2----3)Gal beta(1----4)GlcNAc beta(1----6)-[GlcNAc beta (1----3)]GalNAc-o1; A-3, NeuAc alpha(2----3)Gal beta-(1----4)[Fuc alpha(1----3)]GlcNAc beta(1----3)Gal beta(1----3) GalNAc-o1; A-4, NeuAc alpha(2----3)Gal beta(1----4)[Fuc alpha(1----3)]Glc-NAc NAc beta(1----6)[GlcNAc beta(1----3)]GalNAc-o1; A-6,NeuAc alpha-(2----3) Gal beta(1----4)[Fuc alpha(1----3)]GlcNAc beta(1----6)[Gal beta-(1----4) GlcNAc beta(1----3)]GalNAc-o1. The simultaneous presence of sialic acid in alpha(2----3)-linkage to Gal and fucose in alpha(1----3)-linkage to GlcNAc of the same N-acetyllactosamine unit could be adequately proved by high resolution 1H NMR spectroscopy. This sequence constitutes a novel structural element for mucins.  相似文献   

16.
J Petryniak  I J Goldstein 《Biochemistry》1986,25(10):2829-2838
Evonymus europaea lectin precipitated with alpha DGal(1----3) beta DGal(1----4)beta DGlcNAc-bovine serum albumin (BSA), alpha LFuc(1----2)beta DGal(1----3)beta DGlcNAc-BSA, alpha LFuc(1----2)beta DGal(1----4)DGlcNAc, and alpha DGal(1----3)[alpha LFuc(1----2)]beta DGal-BSA. However, the lectin neither precipitated with alpha LFuc(1----2)-beta DGal-BSA, alpha DGal(1----3)beta DGal-BSA, or beta DGal(1----4)beta DGlcNAc-BSA nor agglutinated erythrocytes of Oh phenotype having multiple terminal beta DGal(1----4)beta DGlcNAc residues. These results indicate that the minimal structural requirement for glycoprotein precipitation or cell agglutination by the lectin includes any of the three trisaccharides (fucosylated or nonfucosylated) derived from the blood group B tetrasaccharide. The monosaccharides linked to the beta-D-galactosyl residue in the blood group B tetrasaccharide, namely, alpha-D-galactose, alpha-L-fucose, and N-acetyl-beta-D-glucosamine, participate almost equally in binding to the lectin in as much as removal of any one of these sugars reduces the inhibiting potency of the resulting trisaccharide. alpha LFuc(1----2)beta DGal(1----3)beta DGlcNAc-BSA (H type 1) and alpha LFuc(1----2)beta DGal(1----4)beta DGlcNAc (H type 2) were precipitated to the same extent. The E. europaea lectin neither precipitated alpha DGal(1----4)-beta DGal(1----4)beta DGlcNAc-BSA, Lea-BSA, Leb-BSA, or beta DGlcNAc(1----4)[alpha LFuc(1----6)]beta DGlcNAc-BSA nor agglutinated Oh,Lea and Oh,Leb erythrocytes, demonstrating that terminal D-galactose linked alpha-(1----4) to subterminal beta-D-galactose, or alpha-L-fucose linked to N-acetylglucosamine, prevents lectin binding. Corey-Pauling-Koltun molecular models, built on the basis of data from 1H NMR and hard-sphere exo-anomeric (HSEA) calculations provided by Lemieux and co-workers [Lemieux, R. U., Bock, K., Delbaere, L. T. J., Koto, S., & Rao, V. S. (1980) Can. J. Chem. 58, 631-653], show that these alpha-D-galactosyl and alpha-L-fucosyl groups act to sterically hinder lectin binding to these oligosaccharides; these observations also suggest that the lectin binds to the beta-side of these oligosaccharides. These sides, on both blood group H type 1 and blood group H type 2 oligosaccharides, provide a similar contour which can fully account for their equal reactivity with E. europaea lectin. The only difference found between Lotus and Ulex I lectins in precipitating ability was that only Lotus precipitated with beta DGlcNAc(1----4)[alpha LFuc(1----6)]beta DGlcNAc-BSA.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

17.
Characterization of major glycolipids in bovine erythrocyte membrane   总被引:10,自引:0,他引:10  
Several neutral glycolipids and gangliosides were isolated from bovine erythrocyte stroma. Their structures were determined by partial acid hydrolysis, methylation analysis, periodate oxidation and CrO3 oxidation. Two major neutral glycolipids were characterized as lactosylceramide and galactosyl(alpha1--3)galactosyl(beta1--4)N-acetylglucosaminyl(beta1--3)galactosyl(beta1--4)glucosyl(beta1--1)ceramide. Two major gangliosides were N-glycolylneuraminosyl(2--3)galactosyl(beta1--4)glucosyl(beta1--1)ceramide and N-glycolylneuraminosyl(2--3)galactosyl(beta1--4)N-acetylglucosaminyl(beta1--3)galactosyl(beta1--4)glucosyl(beta1--1)ceramide. Minor glycolipids were glucosyl- and galactosylceramide, glucosamine-containing tri- and tetraglycosylceramide, glucosamine-containing disialosylhexaglycosylceramide, and gangliosides containing N-acetylneuraminic acid. The ceramide moiety of each glycolipid contained perdominantly d18:1 sphingosine, and normal fatty acids of C16:0, C22:0, C24:0, and C24:1.  相似文献   

18.
An enzyme which catalyzes the conversion of GlcNAc-PP-undecaprenol into ManNAc(beta 1----4)GlcNAc-PP-undecaprenol, a key lipid intermediate in the de novo synthesis of various teichoic acids, was partially purified from the 20,000 x g supernatant fraction of Bacillus subtilis AHU 1035 cell homogenate. By means of ammonium sulfate precipitation, gel chromatography, and ion-exchange chromatography, the enzyme was purified about 70-fold, giving a preparation virtually free from substances obstructive to measurement of the N-acetylmannosaminyltransferase reaction. The enzyme was shown to be specific to UDP-ManNAc. The Km value for UDP-ManNAc was 4.4 microM, and the optimum pH was 7.3. The enzyme required 10 mM MgCl2, 0.3 M KCl, 25% glycerol, and 0.1% Nonidet P-40 to function at full activity.  相似文献   

19.
Glycoprotein MII2, the major cell surface glycoprotein (molecular mass 110 kDa) of Zajdela hepatoma ascites cells, contains about 25 O-glycosidic oligosaccharide chains per molecule. They were released as oligosaccharide-alditols by alkaline borohydride treatment of MII2, and purified by gel filtration on Bio-Gel P-6 followed by high-voltage paper electrophoresis. Four oligosaccharide-alditol fractions (A-D) were obtained in relative yields of 8:6:3:3. The structure of the components of fractions A-C was determined by 500-MHz 1H-NMR spectroscopy in combination with sugar composition analysis, to be as follows. (A) NeuAc alpha(2----3)Gal beta(1----3)[NeuAc alpha(2----3)Gal beta(1----4)GlcNAc beta(1----6)]GalNAc-ol; (B1) NeuAc alpha(2----3)Gal beta(1----3)[Gal beta(1----4)GlcNAc beta(1----6)]GalNAc-ol; (B2) Gal beta(1----3)[NeuAc alpha(2----3)Gal beta(1----4)GlcNAc beta(1----6)]GalNAc-ol; (C) NeuAc alpha(2----3)Gal beta(1----3)GalNAc-ol. On the basis of sugar composition and characteristics on Bio-Gel P-6 filtration, paper electrophoresis and thin-layer chromatography, the structure of the carbohydrate component of fraction D is proposed to be as follows. (D) NeuAc alpha(2----3)Gal beta(1----3)[NeuAc alpha(2----6)]GalNAc-ol  相似文献   

20.
Structures of glycolipids isolated from human granulocytes were elucidated by fast atom bombardment-mass spectrometry, methylation analysis, and exo- and endoglycosidase treatment. All neutral glycolipids, with saccharide residues ranging from 2 to 10, were found to have linear N-acetyllactosaminyl backbones. The majority of neutral glycolipids contain one or two fucosyl residues attached to N-acetylglucosamine residues through the Fuc alpha 1----3 linkage and were reactive with the monoclonal antibody specific to Gal beta 1----4(Fuc alpha 1----3)GlcNAc, the Lex structure. Their general structure can be expressed as follows: (formula; see text) where n = 0-3. Glycolipids containing sialic acid (gangliosides) were also found to have linear N-acetyllactosaminyl backbones with sialic acid joined to this backbone by either alpha 2----3 or alpha 2----6 linkage. The gangliosides have the following general structure: (formula; see text) where n = 0-3. The ceramide was composed of sphingosine with d18:1 as the long-chain base and C16:0 (as a major component) or C24:1 (as a minor component) fatty acid. Analysis of glycolipids isolated from granulocytes, erythrocytes, and whole blood cells revealed that, among the glycolipids prepared from the whole blood cells, dihexaosylceramide, lactoneotetraosylceramide, and the above described linear lactoneo series neutral glycolipids are present in granulocytes but barely present in erythrocytes.  相似文献   

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