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K Jann

Publications and source records attributed to K Jann.

At least 145 records · Page 8Linked to original sources
PubMed1978

Citrobacter O-antigens: structure of the O-antigenic polysaccharide from Citrobacter sp. 396.

The structure of the O-specific polysaccharide moiety of the lipopolysaccharide from Citrobacter 396 was elucidated by composition, methylation, and periodate oxidation studies. The repeating unit consists of four 2-linked mannoses and one 3-linked N-acetylglucosamine. One of the mannose units is substituted at C3 with alpha-glucose, and one is substituted at C3 with alpha-(2-O-acetyl)-abequose. All the mannosyl linkages appear to have the beta-configuration; the N-acetylglucosaminyl linkage has the alpha-configuration. In bacterial agglutination and passive hemagglutination in some Salmonella antisera, Citrobacter 396 as well as its O-antigenic lipopolysaccharide expressed the serological factors 5 and 6. In corroboration of our structural studies, this showed the presence of alpha-(2-O-acetyl)-abequosyl-1,3-mannose (factor 5) and alpha-glucosyl-1,3-mannose (factor 6).

Antigens, Bacterial↗
PubMed1977

Cell-wall lipopolysaccharide of the 'Shigella-like' Escherichia coli 058. Structure of the polysaccharide chain.

Two lipopolysaccharide preparations were obtained from Escherichia coli 058 by extraction with 45% aqueous phenol and fractional precipitation with cetyltrimethyl ammonium bromide (Cetavlon). Chemical analysis and polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate showed that the two preparations differed only in the extent of the O-specific polysaccharide moiety. The O-specific polysaccharide was characterized with proton magnetic resonance and infrared spectroscopy, optical rotation and paper electrophoresis. Using gas-liquid chromatography and ion-exchange chromatography, it was shown to contain D-mannose, 2-acetamido-2-deoxy-D-glucose, 3-O-(R-1'-carboxyethyl)-L-rhamnose (rhamnolactylic acid), and O-acetyl groups in the molar ratios of 2:1:1:1. The polysaccharide and oligosaccharides obtained from it were subjected to methylation and chromic acid oxidation. The results obtained indicated that the polysaccharide consists of tetrasaccharide repeating units in which the trisaccharide beta-GlcNAc1 - 4alphaMan-1 - 4(2/3-O-Ac)-Man is substituted at C-3 of the non-acetylated mannose with rhamnolactylic acid. The repeating units are joined through alpha-mannosyl-1 - 3-glucosamine bonds. This structure is identical with that of the cell wall polysaccharide of Shigella dysenteriae type 5.

Carbohydrates↗
PubMed1977

Genetic determinants of the synthesis of the polysaccharide capsular antigen K27(A) of Escherichia coli.

Most of the his+ hybrids from crosses between the Escherichia coli donor Hfr45(O8:K27) and different E. coli O9 recipients expressed the donor O8 antigen specificity and produced the capsular antigen K27. Therefore these hybrids must have inherited the his-linked donor rfb region determining the synthesis of O8- specific polysaccharides as well as his-linked genes involved in K27 antigen synthesis. In the living state these hybrids were inagglutinable in O8 antiserum like the donor cells. However, when E. coli K12 and O8:K42- were used as recipients most of the his+ hybrids were agglutinable in O8 and K27 antisera. The amounts of K27 antigen present in these hybrids, designated as K27i (intermediate) forms, were sufficient to evoke the production of K27 antibodies in rabbits, but insufficient to inhibit O-agglutination of the respective cells. The additional transfer of the trp region of E. coli O8:K27 into such K27i forms frequently resulted in O-inagglutinable K27+ hybrids. This is attributed to the introduction of trp-linked genes which apparently play a role in the synthesis of K27 capsular antigen. Tus it is concluded that at least two gene loci, one close to his and the other close to trp, are required for the synthesis of the complete capsular antigen K27.

Antigens, Bacterial↗
PubMed1977

Mitogenic stimulation of murine spleen cells: relation to susceptibility to Salmonella infection.

The screening of several inbred strains of mice suggested that the capacity of their spleen cells to respond to the mitogenic effect of lipopolysaccharide (LPS) of gram-negative bacteria was correlated with their resistance to intraperitoneal infection with Salmonella typhimurium. An infection of LPS into mice caused changes in the in vitro responsiveness of their spleen cells to the mitogenic effects of LPS and phytohemagglutinin. Pretreatment of mice with whole ultraviolet (UV)-killed bacteria led to a marked rise in the in vitro response of the spleen cells to UV-killed bacteria, but not to LPS or or phytohemagglutinin. This enhanced response to UV-killed bacteria was not specific for the O antigens of the bacteria.

Animals↗
PubMed1976

The cell-wall lipopolysaccharide of Escherichia coli K-12. Structure and acceptor site for O-antigen and other substituents.

The lipopolysaccharides of two wild-type Escherichia coli K-12 strains, two core-deficient mutants and one SR recombinant with Salmonella typhimurium specificity were analyzed. The respective oligosaccharides were dephosphorylated and methylated. Chemical analysis of the oligosaccharides and mass spectrometric analysis of their methylated derivatives indicated the presence of core structures with different degrees of completion. In different strains of E. coli K-12 the complete core is substituted at the non-reducing end with N-acetylglucosamine or with another substituent. There are indications that the latter may be N-acetylmannosaminuronic acid. In the SR recombinant the complete (N-acetylglucosamine-free) K-12 core is substituted with one S-specific oligosaccharide of S. typhimurium. The attachment site for all these substituents is the 6-position of the non-reducing core-terminal glucose. The heterogeneity of the K-12 core preparations and mode and nature of their substitution are discussed.

Antigens, Bacterial↗
PubMed1976

The O9 antigen of Escherichia coli. Structure of the polysaccharide chain.

The lipopolysaccharide from Escherichia coli O9:K30- was isolated in about 2% yield with aqueous 45% phenol at 65 degrees C, followed by ultracentrifugation. The polysaccharide moiety was obtained by graded hydrolysis and gel permeation chromatography. It consisted of a mannan which carried on its reducing end the core oligosaccharide of the R1 type. The mannan contained 1 leads to 2 and 1 leads to 3 linkages in a ratio of 3:2, as determined by methylation analysis and mass spectrometry. On periodate oxidation, 58% of the mannose residues were destroyed. Degradation of oligosaccharide mixtures with alpha-mannosidase from jack bean meal, as well as a specific rotation of [alpha]25D = +89 degrees indicated that all mannosyl linkages have the alpha-configuration. Smith degradation resulted in the liberation of mannosyl (1 leads to 3)-mannose (bound to glyceraldehyde), as established by methylation analysis. From these results we conclude that the O9 polysaccharide of E. coli has a pentasaccharide repeating unit of alpha-mannosyl(1 leads to 3)-alpha-mannosyl-(1 leads to 2)-alpha-mannosyl-(1 leads to 2)-alpha-mannosyl-(1 leads to 2)-mannose, which are joined in the polysaccharide through alpha-(1 leads to 3)-mannosyl linkages.

Chromatography, Gas↗
PubMed1976

Cell-wall lipopolysaccharides of ampicillin-resistant mutants of Escherichia coli K-12.

The lipopolysaccharides of ampicillin-resistant cell-wall-defective mutants of Escherichia coli K-12 were analyzed. From their lipopolysaccharides the respective core oligosaccharides were obtained. Following dephosphorylation,the core oligosaccharides were methylated and analyzed by gas chromatography/mass spectrometry. From core-defective mutants substructures of the K-12 core were obtained. Analysis of the lipopolysaccharide preparations from wild-type K-12 indicated the presence of several core structures with different degrees of completion. The lipopolysaccharide preparation was degraded and the oligosaccharide mixture was partially resolved by gel filtration chromatography. Methylation, gas chromatography and mass spectrometry of the oligosaccharides permitted the tentative formulation of the K-12 core structure. Alternative interpretations for this heterogeneity are discussed.

Ampicillin↗
PubMed1976

Cell-wall lipopolysaccharide of the 'Shigella-like' Escherichia coli 0124. Structure of the polysaccharide chain.

From Escherichia coli 0124 two lipopolysaccharide preparations were obtained with phenol/water extraction and cetavlon precipitation. Polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate and chemical analysis showed that the two preparations from E. coli 0124 and the corresponding preparations from Shigella dysenteriae type 3 reacted alike. The O-specific polysaccharide moiety was characterized with proton magnetic resonance spectroscopy, optical rotation and paper electrophoresis. The constituents were determined by gas chromatography and ion-exchange chromatography. The polysaccharide contained glucose (Glc), galactose (Gal), galactosamine (GalN) and 4-O-(1'-carboxyethyl)-D-glucopyranose (glucolactilic acid, GlcLA) in the molar ratios of 1:2:1:1. Glucolactilic acid, which has a structure similar to muramic acid, was first found in Sh. dysenteriae. The polysaccharide from E. coli 0124 and oligosaccharides obtained from it by partial acid hydrolysis were subjected to methylation analysis using the method of combined gas chromatography--mass spectrometry. The results indicated that the pentasaccharide repeating unit of the polysaccharide is (see article). In the polysaccharide the repeating units are joined through galactofuranosidic linkages. This structure is identical with that of the somatic polysaccharide of Sh. dysenterae type 3.

Cell Wall↗
PubMed1976

Genetic transfer of Salmonella O antigens to Escherichia coli O8.

His+ hybrids from a cross between a Salmonella typhimurium donor and an Escherichia coli O8 recipient expressed E. coli O8 specificity and in addition Salmonella O4,12-specificity. This indicated that the recipients had received the his-linked donor rfb cluster determining the synthesis of S. typhimurium O-specific repeat units and that the rfb genes of both mating partners are functional in these hybrids. Chemical analyses showed that the hybrids contained an E. coli O8 lipopolysaccharide (O antigen) and a S. typhimurium specific lipopolysaccharide with only one O-specific repeat unit (SR antigen). O8-negative mutants selected from the O8-positive hybrids retained the Salmonella O-specificity and represent semi-rough (SR) forms, because the rfc gene(s) determining the polymerization of repeat units has not been transferred. Attempts to introduce the S. typhimurium rfc locus into E. coli O8 remained unsuccessful. Crosses between a S. typhi donor and E. coli O8 gave rise to smooth (S) and SR His+ recombinants exhibiting only S. typhi O-specificity. The smooth recombinants are assumed to have obtained the his-linked rfb cluster and in addition the rfc gene(s) of the donor. The exchange of the rfb region of such smooth recombinants by that of a S. typhimurium donor led to smooth hybrids with O4,(5), 12-specificity. The phenotypically smooth recombinants exhibited concomitantly S- and SR-lipopolysaccharides of S. typhi and S. typhimurium O-specificity, respectively.

Antigens, Bacterial↗
PubMed1976

Enzymatic action of coliphage omega8 and its possible role in infection.

The receptor of coliphage omega8 is the O-specific mannan of Escherichia coli O8 in which the trisaccharide alpha-mannosyl-1,2-alpha-mannosyl-1,2-mannose is joined through alpha-mannosyl-1,3-linkages. Coliphage omega8 produces an endo-alpha-1,3-mannosidase which destroys the receptor, liberating a series of oligosaccharides (repeating trisaccharide and multiples). The enzyme is an integral part of the phage particles and also occurs in a free form in the lysates. Phage particles hydrolyze alpha-1,3-mannosyl linkages in the lipopolysaccharide, the polysaccharide (mannan) moiety, and higher oligosaccharides with an efficiency decreasing in this order. No transmannosylation could be detected. Phage particles also degrade the receptor mannan on whole bacteria, as determined with 14C-labeled E. coli O8. The values of Km and Vmax were determined with omega8 particles and free enzymes using native lipopolysaccharide and its triethylammonium salt. The latter, which was obtained after electrodialysis, has a micellar weight of 2.5 X 10(5), whereas the native lipopolysaccharide forms supermicelles with micellar weights of several millions. With coliphage omega8 as enzyme and supermicellar lipopolysaccharide as substrate Km=5 X 10(-8) M was obtained. This, together with the fact that omega8 attaches irreversibly to E. coli O8, was used in proposing a hypothesis for the possible role of the enzyme in the first steps of infection with coliphage omega8.

Adsorption↗
PubMed1975

Heterogeneity of lipopolysaccharides. Analysis of polysaccharide chain lengths by sodium dodecylsulfate-polyacrylamide gel electrophoresis.

Lipopolysaccharide preparations from R(rough) Escherichia coli O8-,SR(semirough) Salmonella typhimurium and S (smooth) strains E. coli O8 and Citrobacter 396 were disintegrated with sodium dodecylsulfate and subjected to polyacrylamide gel electrophoresis in the presence of 1% sodium dodecylsulfate. The results obtained were compared with those obtained from the same lipopolysaccharide preparations by degradation analysis. In dodecylsulfate gel electrophoresis the lipopolysaccharide preparation from the E. coli R mutant and the S. typhimurium SR mutant showed one band each (R-and SR-band, respectively) with different electrophoretic mobilities. The lipopolysaccharide preparations from the E. coli O8-strain exhibited two bands, one of which had the same electrophoretic mobility as the R-band and the other was identified as S-band. The lipopolysaccharide preparation from the Citrobacter 396-S-strain exhibited four bands: one R-band, one SR-band and two S-bands. The results showed that wild-type S strains contain more than one type of lipopolysaccharide. They differ in the length of their O-specific polysaccharide chains. The lipid A content of the different lipopolysaccharide was expressed in their electrophoretic mobilities.

Citrobacter↗
PubMed1975

Cell-wall lipopolysaccharide from Escherichia coli B.

The lipopolysaccharide of Escherichia coli BB and a number of R-phage selected (e.g. T3, T4) cell-wall-defective mutants were analyzed. From their lipopolysaccharides the respective core oligosaccharides were obtained. Following dephosphorylation, the oligosaccharides were methylated and analyzed by gas chromatography/mass spectrometry. This revealed the sugar sequence in the hexose-heptose region of the core. The linkage of heptose (Hep) to 2-keto-3-deoxyoctonate (KDO) was established as ... Hep 1,5 leads to KDO ... by methylation analysis. The substituted derivative of KDO was identified by gas chromatography and mass spectrometry. The KDO region contains three KDO units. Its structure was elaborated by (a) selective removal and identification of 7-phosphoryl ethanolamine-KDO (KDO-PN), (b) periodate oxidation and thiobarbituric acid reaction in conjunction with mild hydrolysis, (c) a modified methylation analysis. Phosphate substitution of E. coli BB core was studied by beta-elimination and using the information obtained with KDO-PN. The structures of the cell wall lipopolysaccharides from E. coli BB and cell-wall-defective mutants are given.

Chromatography, Gas↗