ABSTRACT
O-specific-polysaccharide and core oligosaccharide were isolated from Citrobacter strain PCM 1487 lipopolysaccharide and purified. The polysaccharide was selectively devoid of 4-deoxy-D-arabinohexose residues. Covalent conjugates of the modified O-specific polysaccharide and of the core oligosaccharide with tetanus toxoid were prepared. Immunochemical characterization of these conjugates proved that they are strong immunogens. Using monospecific rabbit antisera raised against the conjugates, the antigenic relationships between lipopolysaccharides of various strains of Citrobacter, Shigella sonnei, and Shigella flexneri were studied by quantitative microprecipitin and quantitative microprecipitin inhibition and immunoblotting tests.
Subject(s)
Citrobacter/immunology , Polysaccharides, Bacterial/immunology , Bacterial Proteins/chemistry , Bacterial Proteins/immunology , Carbohydrate Sequence , Citrobacter/chemistry , Immunochemistry , Lipopolysaccharides/chemistry , Lipopolysaccharides/immunology , Molecular Sequence Data , O Antigens , Oligosaccharides/chemistry , Oligosaccharides/immunology , Polysaccharides, Bacterial/chemistry , Precipitin TestsABSTRACT
Core oligosaccharides (complete and incomplete) isolated from Citrobacter 036 lipopolysaccharide were covalently conjugated with tetanus toxoid. Serological examination of the Citrobacter 036 core oligosaccharide-tetanus toxoid conjugates showed that they are strong immunogens. The monospecific anti-conjugate sera prepared by immunization of rabbits, were used to study the antigenic relations between lipopolysaccharide core regions of 8 strains of Citrobacter. Immunoelectrophoresis, immunoblotting and quantitative microprecipitation were performed in the experiments.
Subject(s)
Citrobacter/immunology , Lipopolysaccharides/immunology , Oligosaccharides/immunology , Tetanus Toxoid/immunology , Animals , Carbohydrate Conformation , Carbohydrate Sequence , Cross Reactions , Epitopes , Immune Sera , Immunoblotting , Immunoelectrophoresis , Immunoglobulin G/biosynthesis , Molecular Sequence Data , Oligosaccharides/chemistry , Precipitin Tests , Rabbits , Tetanus Toxoid/chemistryABSTRACT
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.
Subject(s)
Enterobacteriaceae/analysis , Lipopolysaccharides/isolation & purification , Carbohydrates/analysis , Electrophoresis, Polyacrylamide Gel , Enterobacteriaceae/classification , Sodium Dodecyl Sulfate , Species SpecificityABSTRACT
Shigella sonnei phase II core oligosaccharide (OSPhII) was linked covalently with protein (bovine serum albumin or tetanus toxoid) to obtain a conjugate (OSPhII-protein) of good immunogenicity in rabbits. Anti-OSPhII-protein conjugate sera contained high levels of immunoglobulin G antibodies against the complete core region of Sh. sonnei lipopolysaccharide. The antigenic relationships between lipopolysaccharides of R1, R3 and R4 core types using anti-OSPhII-protein sera were studied. These antisera may be used for the rapid determination of core types in unknown enterobacterial strains.
Subject(s)
Lipopolysaccharides/immunology , Animals , Hemolysis , Immunoassay/methods , Immunodiffusion/methods , Immunoelectrophoresis, Two-Dimensional/methods , Indicators and Reagents , Oligosaccharides/immunology , Rabbits/immunology , Serum Albumin, Bovine , Shigella flexneri/immunology , Shigella sonnei/immunology , Tetanus ToxoidABSTRACT
The methods of limited periodate oxidation and reductive amination were used to obtain covalently linked enterobacterial common antigen (ECA) with tetanus toxoid. This procedure is simple and gives a good yield of the conjugate with high ECA content (molecular ratio of ECA to tetanus toxoid, 6:1). The ECA-tetanus toxoid conjugate is immunogenic in rabbits, in contrast to free ECA or a mixture of ECA with proteins. This conjugate produces high levels of ECA-specific immunoglobulin G antibodies, which can be used as a standard serum.
Subject(s)
Antigens, Bacterial/isolation & purification , Enterobacteriaceae/immunology , Tetanus Toxoid/isolation & purification , Animals , Antibodies, Bacterial/analysis , Antigens, Bacterial/immunology , Cross Reactions , Immunization , Immunologic Techniques , Rabbits , Tetanus Toxoid/immunologyABSTRACT
Shigella sonnei phase I and phase II lipopolysaccharides were examined using passive hemagglutination, immunodiffusion and immunoelectrophoresis. Moreover, O-antigen preparations of phase I obtained by three different methods were separated in SDS polyacrylamide gel electrophoresis into two fractions: L1 and L2, whereas phase II lipopolysaccharide showed one fraction (LI) only. The results of the serological investigations of three mentioned above preparations indicate that the heterogeneity of phase I O-antigen is natural, and not caused by extraction procedures. Shigella sonnei phase I cells produce two types of lipopolysaccharide molecules: I) with core regions substituted by phase I-specific polysaccharide chains, and 2) with core regions unsubstituted, having phase II specificity.
