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E Katzenellenbogen

Publications and source records attributed to E Katzenellenbogen.

At least 37 records · Page 2Linked to original sources
PubMed1994

Serological and structural features of Hafnia alvei lipopolysaccharides containing D-3-hydroxybutyric acid.

The serological heterogeneity of Hafnia alvei lipopolysaccharides from strains ATCC 13337, 1187, 1221, 114/60, 1211 and 1216, that contain D-3-hydroxybutyric acid, was analyzed by rocket immunoelectrophoresis, immunoblotting and passive hemagglutination. The significance of D-3-hydroxybutyric acid component for their cross-reactivity has been discussed. The results obtained allowed us to place four H. alvei strains (ATCC 13337, 1187, 1221 and 114/60) in one serotype (A) and to consider two other strains (1211 and 1216) as separate serotypes (B and C, respectively).

3-Hydroxybutyric Acid↗
PubMed1993

3-Deoxy-octulosonic acid-containing trisaccharide fragment of an unusual core type of some Hafnia alvei lipopolysaccharides.

The 3-deoxy-octulosonic acid-containing trisaccharide was isolated from the carbohydrate material obtained after the acid hydrolysis of lipopolysaccharides of Hafnia alvei strains 2 and 1211 using gel filtration. For purification the trisaccharide fraction was rechromatographed on a Bio-Gel P2 column. On the basis of sugar and methylation analyses and 1H NMR spectroscopy the trisaccharide was identified as 3-deoxy-7-O-(6-O-acetyl-alpha-D-galactopyranosyl)-4-O-(alpha-L-glycero-D - mannoheptopyranosyl)-D-manno-2-octulopyranosic acid. The occurrence of such bifurcate Kdo-containing structure has not been previously reported in Enterobacteriaceae.

Carbohydrate Sequence↗
PubMed1992

The structure of a glycerol teichoic acid-like O-specific polysaccharide of Hafnia alvei 1205.

The O-specific polysaccharide of Hafnia alvei 1205 contained D-glucose, D-galactose, 2-acetamido-2-deoxy-D-glucose, 4-acetamido-4,6-dideoxy-D-glucose (Qui4NAc), glycerol, phosphate, and O-acetyl groups. On the basis of 1D and 2D shift-correlated homonuclear and 13C-1H heteronuclear NMR spectroscopy, methylation analysis, Smith degradation, and dephosphorylation with hydrofluoric acid, it was concluded that the O-antigen was a partially O-acetylated teichoic acid-like polysaccharide having the following structure: [formula: see text]

Carbohydrate Conformation↗
PubMed1991

O-specific polysaccharide of Hafnia alvei lipopolysaccharide isolated from strain 1211. Structural study using chemical methods, gas-liquid chromatography/mass spectrometry and NMR spectroscopy.

The Hafnia alvei strain 1211 O-specific polysaccharide is composed of 3-amino-N-(D-3'-hydroxybutyryl)-3,6-dideoxy-D-galactose, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine and D-glucose (1:1:2:2). On the basis of sugar and methylation analyses, Smith degradation, and one- and two-dimensional 1H- and 13C-NMR spectroscopy, the polysaccharide was shown to be an O-acetylated polymer of the repeating hexasaccharide unit, ----2D(4-OAc)Fucp3NAcyl beta 1----6DGlcpNAc alpha 1---- (DGlcp beta 1----3)4DGalpNAc alpha 1----3DGlcpNAc beta 1----2DGlcp beta 1----, where DFucp3NAcyl = 3-amino-N-(D-3'-hydroxybutyryl)-3,6-dideoxy-D- galactopyranose. The O-specific polysaccharide showed some microheterogeneity due to incomplete substitution by terminal glucose.

Acetylgalactosamine↗
PubMed1991

Core region of Citrobacter O23 lipopolysaccharide. Structure elucidation by chemical methods, gas chromatography/mass spectrometry and NMR spectroscopy at 500 MHz.

A novel enterobacterial core region in Citrobacter O23 lipopolysaccharide is described. Its structure was determined by methylation analysis/mass spectrometry, chemical degradation and one- and two-dimensional 1H-NMR spectroscopy: [formula; see text] where PPEtN stands for diphosphorylethanolamine, and dOclA for 3-deoxy-D-manno-octulosonic acid.

Citrobacter↗
PubMed1990

The structure of the biological repeating unit of the O-antigen of Hafnia alvei O39.

On mild acid-catalysed degradation of the lipopolysaccharide from Hafnia alvei O39 followed by gel filtration of Sephadex G-50, the O-specific polysaccharide and three oligosaccharides were obtained, which represent the core substituted with 0-2 O-antigen repeating-units. On the basis of sugar and methylation analyses, 13C-n.m.r. data, solvolysis of the polysaccharide with anhydrous hydrogen fluoride, and computer-assisted 13C-n.m.r. analysis of the Smith-degraded polysaccharide, it was concluded that the biological repeating unit of the O39 antigen was Formula; see text

Antigens, Bacterial↗
PubMed1990

Structural studies on Hafnia alvei 114-60 O-antigen.

The structure of Hafnia alvei 114-60 O-antigen has been established using sugar and methylation analyses as well as 1H-NMR spectroscopy. The results obtained proved that the repeating unit of Hafnia alvei 114-60 O-antigen is identical to that of Hafnia alvei ATCC 13337 standard strain and has the following structure: [formula: see text]

Antigens, Bacterial↗
PubMed1988

The structure of the O-specific polysaccharide chain from Citrobacter O23-lipopolysaccharide.

The structure of Citrobacter O23-specific polysaccharide has been shown by sugar and methylation analyses of the native and chemically degraded polysaccharide and by 1H- and 13C-n.m.r. spectroscopy to consist of the tetrasaccharide repeating-units: ----4)-alpha-D-Man-(1----2)-alpha-D-Man-(1----2)-beta-D-Man- (1----3)-alpha-D-GalNAc-(1----, 80% of which are substituted by O-acetyl groups.

Antigens, Bacterial↗
PubMed1988

Hafnia alvei lipopolysaccharides: isolation, sugar composition and SDS-PAGE analysis.

Lipopolysaccharides (LPS) of 33 strains of Hafnia alvei were isolated and purified. LPS content of the dry bacterial mass ranged from 1.2 to 4.5%. All examined lipopolysaccharides contained glucose, glucosamine, heptose, 3-deoxy-octulosonic acid and often galactose. Rhamnose, mannose, galactosamine, mannosamine and unidentified amino sugars were found in some H. alvei strains. Sialic acid was present in LPS of one strain. D-3-Hydroxybutyryl groups also were identified in lipopolysaccharides of 5 strains of this genus. SDS-PAGE of the lipopolysaccharides was presented in the paper. According to these results two core types exist in H. alvei.

Carbohydrates↗
PubMed1988

The heterogeneity of lipopolysaccharides from Citrobacter 023 serotype.

Chemical studies on carbohydrate part of lipopolysaccharides isolated from Citrobacter 87/57 and Citrobacter 1556 strains (serotype 023) were carried out. Lipopolysaccharides (LPS) were hydrolyzed with 1% acetic acid and the carbohydrate material was fractionated on Sephadex G-50 and Bio-Gel P-4 columns. All fractions obtained were subjected to chemical analysis by colorimetric methods and by gas-liquid chromatography. It was found that O-specific polysaccharide from LPS 87/57 is composed of mannose and N-acetylgalactosamine in the molar ratio of 3:1. Both lipopolysaccharides contain unsubstituted core oligosaccharides (built of heptose, glucose and galactose in molar ratio of 3:3:1) as well as core oligosaccharides substituted with shorter (LPS 87/57 and LPS 1556) and longer (LPS 87/57) O-specific oligosaccharides. Strain 87/57 is of S (smooth) type and strain 1556 lacking O-specific polysaccharide is of SR (semi-rough) type. The data of Sephadex G-100 chromatography showed that O-antigen from Citrobacter 87/57 is heterogeneous; it contains polysaccharide chains of different length but the same composition. The heterogeneity of Citrobacter 023 lipopolysaccharides has been also detected by SDS-polyacrylamide gel electrophoresis.

Acetylgalactosamine↗
PubMed1987

Structure of the complex group-specific polysaccharide of group B Streptococcus.

The group-specific antigen was isolated from a type Ia group B streptococcal strain and is a complex polysaccharide composed of alpha-L-rhamnopyranosyl, alpha-D-galactopyranosyl, 2-acetamido-2-deoxy-beta-D-glucopyranosyl, D-glucitol, and phosphate residues. The complexity of the group B polysaccharide antigen is evident from the fact that when depolymerized by basic hydrolysis it yielded three structurally related, but nevertheless significantly different, oligosaccharides. These oligosaccharides were obtained in different molar quantities as their monophosphate esters. This evidence strongly suggests that they are linked by phosphodiester bonds in the original group B antigen. If these oligosaccharides are in fact randomly situated throughout the linear polysaccharide, then this type of heterogeneous repeating unit is unusual for a polysaccharide of bacterial origin. However, this structural arrangement of the oligosaccharides has yet to be unambiguously established because the alternate explanation of there being three different polysaccharides in the group B antigen cannot be discounted in the evidence presented here. The oligosaccharides were enzymatically dephosphorylated, and the structures of two of the three oligosaccharides are (formula: see text) Despite their structural differences, the two oligosaccharides are related by the smaller being an integral part of the larger. In the structural analysis of the group B antigen, methylation analysis, periodate oxidation, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, fast atom bombardment mass spectrometry, and various specific chemical and enzymatic degradations were the principal methods used. Of particular interest was the use of an alpha-rhamnosidase to selectively degrade the larger oligosaccharide. This facilitated the assignment of signals in its 1H and 13C NMR spectra.

Carbohydrate Conformation↗
PubMed1985

Immunochemical analysis of the types Ia and Ib group B streptococcal polysaccharides.

The types Ia and Ib group B streptococcal type-specific polysaccharides have remarkable immunologic differences despite a great deal of structural similarity. Although these two complex polysaccharides differ only by a single glycosidic linkage, they are antigenically distinct. Furthermore, terminal sialic acid residues appear to be critical to the immunodeterminant on the type Ia polysaccharide, whereas the antigenicity of the type Ib polysaccharide does not show this dependence on sialic acid. In the current investigation we defined better the immunodeterminant of these polysaccharides. With homologous rabbit antiserum, the type Ia native and core polysaccharides demonstrated partial serologic identity, whereas the type Ib native and core polysaccharides demonstrated complete serologic identity. Surprisingly, the type I degalactosylated polysaccharide, degraded structure, was capable of reacting with a population of antibodies present in type Ia antiserum similar to the complete type Ia native polysaccharide, although demonstrating a reduced level of immunodeterminant expression. Unlike the reactions of the type Ia polysaccharides with homologous rabbit antiserum, the Ib native and core polysaccharides were able to react with identical populations of antibodies in type Ib-specific antiserum. A minor population of antibodies was demonstrated in the type Ib antiserum, which was reactive with the degalactosylated polysaccharide. That a population of antibodies reactive toward the degalactosylated polysaccharide is present in both type Ia and type Ib antisera suggests that the Iabc cross-reacting determinant is due to the presence of serum antibodies reactive with this trisaccharide repeating unit, which is shared by both the type Ia and the type Ib native and core polysaccharides.

Animals↗
PubMed1984

Improved procedures for the conjugation of oligosaccharides to protein by reductive amination.

The rate of coupling of oligosaccharides having aldose end groups to protein by reductive amination was significantly increased by changing the temperature and pH of the reaction, and even more significantly by the addition of borate ions. Under optimized conditions half of the lysine residues of bovine serum albumin could be derivatized by lactose in 7 h and their complete derivatization was achieved in approximately 24 h. All attempts to carry out similar reductive amination procedures using oligosaccharides having ketose (D-fructose, 3-deoxy-D-manno-octulosonic acid (KDO), and sialic acid) failed owing to the slowness of the reaction. Model studies on the coupling of D-fructose and KDO to glycine indicate that any coupling procedure based on reductive amination of ketose residues would of necessity require the prior introduction of a small functionalized spacer molecule.

Amination↗
PubMed1983

Structural determination of the capsular polysaccharide of Streptococcus pneumoniae type 19A (57).

The structure of the Pneumococcus type 19A (57) capsular polysaccharide has been reinvestigated by using methylation analysis and n.m.r. spectroscopy. It is composed of residues of 2-acetamido-2-deoxy-D-mannose, D-glucose, L-rhamnose, and phosphate in the molar ratios of 1:1:1:1. The polysaccharide is linear, and is composed of these components in a repeating unit of the following structure. ---- 4)-beta-D-ManpNAc-(1 ---- 4)-alpha-D-Glcp-(1 ---- 3)-alpha-L- Rhap-(1-PO4-) ---- The type 19A polysaccharide (Na+ salt) was depolymerized by heating it in water at 100 degrees, conditions that also hydrolyzed the newly formed phosphoric monoesters.

Carbohydrate Sequence↗
PubMed1983

Immunochemical analysis and immunogenicity of the type II group B streptococcal capsular polysaccharide.

The relationship between group B streptococcal (GBS) type-specific antisera and the type II-specific polysaccharide is evaluated from a structural and immunologic viewpoint. Although all GBS type-specific polysaccharides are composed of the same monosaccharides, the type II antigen is more complex structurally and contains these sugars in a molar ratio different from the other antigens. Type II polysaccharide has two side chains. One contains only sialic acid and is less susceptible to acid cleavage than sialic acid residues found on types III, Ia, and Ib polysaccharides. The other side chain is composed of galactose as the only sugar. Immunochemical studies demonstrate that the type II polysaccharide has several immunodeterminants. One of these determinants is likely to be the side-chain galactose, while sialic acid appears to comprise part of another immunodeterminant, more complex than sialic acid alone. A series of cross-reactions is demonstrated between the type II native antigen and antisera to serotypes Ia, III, and Ib by a sensitive radioactive antigen-binding assay, which account for additional, complex immunodeterminants. The strongest of these cross-reactions is with type Ia antiserum and the weakest with Ib antiserum. Since Ia and Ib polysaccharides differ in only one linkage, these findings suggest that the trisaccharide beta D-N-acetyl-glucosamine-p(1 leads to 3) beta D-galactose-p(1 leads to 4) beta D-glucose-p [[beta D-GlcNAcp(1 leads to 3) beta D-Galp(1 leads to 4)beta D-Glcap]] is the likely common site responsible for the interaction of the type II native polysaccharide and type Ia antiserum. Another cross-reaction is observed between type III antiserum and type II native antigen. Inhibition studies indicate that the most likely cross-reactive determinant in this case is [beta D-Galp(1 leads to 4)beta D-GlcNAcp]. Type II polysaccharide has been utilized in a human vaccine trial to test safety and immunogenicity. The polysaccharide is highly immunogenic, inducing an antibody response in 95% of recipients, and nontoxic, with side-effects confined to minimal local reactions. Despite the cross-reactions observed between type-specific antigens and antibody prepared by immunization of rabbits with whole bacteria, which suggest shared immunodeterminants, similar cross-reactions were not detected in human sera after immunization with purified type II polysaccharide.

Adult↗