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PubMed1982

Immunochemical studies of partially hydrolyzed lipopolysaccharide from Fusobacterium nucleatum ATCC 10953.

Fusobacterium nucleatum ATCC 10953 LPS was split by hydrolysis with 1 per cent acetic acid into acid-soluble polysaccharide and lipid A. Gel filtration of the acid-soluble polysaccharide on Bio-Gel P-60 gave a high-molecular-weight fraction eluted with the void volume (Vo), and a fraction eluted at 2.4 x Vo. The high-molecular-weight fraction was serologically active, and contained glucose as the only sugar. The other fraction, which was serologically inactive, contained L-glycero-D-manno-heptose, galactose, glucosamine, keto-deoxy-octonate, and phosphorus. The fraction eluted at 2.4 x Vo is thought to constitute the polysaccharide core region, whereas the high-molecular-weight fraction may represent O-antigenic side chains.

Chromatography, Gel↗

PubMed1975

Characterization of endotoxin from Fusobacterium necrophorun.

Endotoxic lipopolysachharide (LPS) was obtained from phenol-water extraction of cell walls prepared from mass-cultivated Fusobacterium necrophorum. The LPS was relatively free of nucleic acids and low in protein, and constituted about 4% of the cell walls. Upon acid hydrolysis, some of the components detected were hexosamines (7.0%), neutral and reducing sugars (50.5%), heptose (6.4%), 2-keto-3-deoxyoctonate (0.8%), lipid A (21.0%), and phosphorus (1.7%). Under electron microscopy the LPS appeared mainly as ribbon-like trilaminar structures, and upon chemical treatment it displayed a behavior resembling that reported in certain enterobacterial LPS. The LPS was lethal to mice, 11-day-old chicken embryos, and rabbits. Endotoxicity in mice was enhanced at least 1,380-fold by the addition of 12.5 mug of actinomycin D. Induced tolerance to lethal effect of the endotoxin and rapidly acquired resistance to infection by F. necrophrum viable cells were also demonstrated in mice. The endotoxin produced both localized and generalized Shwartzman reactions as well as biphasic pyrogenic responses in rabbits. These results firmly establish the presence of a classical endotoxin in F. necrophorum, thus providing strong support to our recent suggestion that cell wall-associated components may contribute significantly to the pathogenicity of F. necrophorum.

Animals↗

PubMed1985

Lipopolysaccharide variation in Coxiella burnetti: intrastrain heterogeneity in structure and antigenicity.

We isolated lipopolysaccharides (LPSs) from phase variants of Coxiella burnetii Nine Mile and compared the isolated LPS and C. burnetii cells by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting. The LPSs were found to be the predominant component which varied structurally and antigenically between virulent phase I and avirulent phase II. A comparison of techniques historically used to extract the phase I antigenic component revealed that the aqueous phase of phenol-water, trichloroacetic acid, and dimethyl sulfoxide extractions of phase I C. burnettii cells all contained phase I LPS, although the efficiency and specificity of extraction varied. Our studies provide additional evidence that phase variation in C. burnetii is analogous to the smooth-to-rough LPS variation of gram-negative enteric bacteria, with phase I LPS being equivalent to smooth LPS and phase II being equivalent to rough LPS. In addition, we identified a variant with a third LPS chemotype with appears to have a structural complexity intermediate to phase I and II LPSs. All three C. burnetii LPS contain a 2-keto-3-deoxyoctulosonic acid-like substance, heptose, and gel Limulus amoebocyte lysates in subnanogram amounts. The C. burnetii LPSs were nontoxic to chicken embryos at doses of over 80 micrograms per embryo, in contrast to Salmonella typhimurium smooth- and rough-type LPSs, which were toxic in nanogram amounts.

Bacterial Proteins↗

PubMed1975

Characterization of lipopolysaccharides from Escherichia coli K-12 mutants.

Chemical analyses of the carbohydrate composition of lipopolysaccharides (LPS) from a number of LPS mutants were used to propose a schematic composition for the LPS from Escherichia coli K-12. The formula contains four regions: the first consists of lipid A, ketodeoxyoctonoic acid, and a phosphorous component; the second contains only heptose; the third only glucose; and the fourth additional glucose, galactose, and rhamnose. LPS from E. coli B may have a similar composition but lacks the galactose and rhamnose units. A set of LPS-specific bacteriophages were used for comparing three mutants of Salmonella with a number of LPS mutants of E. coli K-12. The results confirm that there are basic similarities in the first and second regions of the LPS structure; they also support the four region divisions of the LPS formula. Paper chromatography was used for characterization of 32-P-labeled LPS from different strains of E. coli and Salmonella. The Rf values for LPS varied from 0.27 to 0.75 depending on the amounts of carbohydrates in the molecule. LPS from all strains studied was homogenous except for strain D31 which produced two types of LPS. Mild acid hydrolysis of labeled LPS liberated lipid A and two other components with phosphate, one of which was assigned to the first region. It is suggested that paper chromatography can be used in biosynthetic studies concerning regions 2 to 4.

Carbohydrates↗

PubMed1975

Lipophilic O-antigens containing D-glycero-D-mannoheptose as the sole neutral sugar in Rhodopseudomonas gelatinosa.

Lipopolysaccharides (LPS, O-antigens) of 12 strains of the photosynthetic bacterium Rhodopseudomonas gelatinosa were obtained by the phenol/chloroform/petroleum ether method, recommended for extracting lipophilic glycolipids of enterobacterial R-mutants. All R. gelatinosa LPS have essentially the same chemical composition. Similar to LPS of Salmonella R-mutants of chemotypes Rd1 and Rd2, the sole neutral sugar constituent is an aldoheptose. The heptose of R. gelatinosa LPS has the D-glycero-D-manno- configuration, in contrast to the L-glycero-D-mannoheptose of enterobacterial LPS. 2-Keto-3-deoxyoctonate forms the acid-labile linkage between the lipid moiety (lipid A) and the oligosaccharide moiety of R. gelatinosa LPS. Like enterobacterial lipid A, lipid A of this species contains phosphate and D-glucosamine as the sole amino sugar. The fatty acid spectrum conprises beta-hydroxycapric, lauric, and myristic acids. Beta-Hydroxymyristic acid, the typical fatty acid of enterobacterial LPS, is lacking. The R. gelatinosa LPS show O-antigenic acitivity; passive hemagglutinations with untreated or heat-treated (not well alkali-treated) LPS and antisera prepared against heat-killed cells yield high titers. According to the serological cross-reactions observed, the LPS of the 12 strains could be arranged into two different serotypes: serotype I comprising strains 29/1, 29/2, 25/2, and serotype II comprising strains 44/K/6, 3/1, IS/10, 39/2, Dr2, 2150, P8P9, K32, P18f3.1. No serological cross-reactions were observed between LPS of these two different serotypes in passive hemagglutinations.

Caprylates↗

PubMed1967

Endotoxic glycolipid from a heptoseless mutant of Salmonella minnesota.

The endotoxin of a heptoseless mutant of Salmonella minnesota R595 was extracted with phenol-water. Most of this material was found distributed in the insoluble fraction of the extract. The results showed that the R595 endotoxin behaved as a lipid rather than as a lipopolysaccharide (LPS). The preparation, although it does not contain O-specific polysaccharides, does contain 2-keto-3-deoxyoctonic acid (KDO), hexosamine, and several other unidentified compounds. Therefore, the term "glycolipid" is used in this paper instead of lipopolysaccharide. The crude glycolipid fraction, which was soluble in a mixture of chloroform-methanol (8:2), was purified by a procedure including fractionation with organic solvents and by different-column chromatographic methods. Although a chromatographic fraction of the glycolipid showed homogeneity in most systems investigated, the presence of contaminants could not be excluded. Chemical analysis of the glycolipids showed the absence of hexoses and heptoses. Constituents which were found were hexosamine, KDO, fatty acids, and phosphorus, which showed a relatively simple chemical composition. Partial acidic hydrolysis of the glycolipid yielded hexosamine-phosphates, as described in "Lipid A" fractions of smooth LPS preparations. Thin-layer chromatography of the partially hydrolyzed glycolipid showed a pattern similar to "Lipid A" fractions of other strains. The biological activity of the glycolipid was at the same level as that of other gram-negative endotoxins. Pyrogenicity, Shwartzman reactivity, and chick embryo ld(50) values were as high or higher than those of purified Serratia marcescens endotoxin preparations, but mouse ld(50) measurements gave significantly lower results.

Amino Acids↗

PubMed1976

Preparation and chemical properties of the outer membrane of a moderately halophilic gram-negative bacterium.

Outer membranes, almost free from peptidoglycan components, were prepared from a moderately halophilic gram-negative bacterium grown in a medium containing 2 M NaCl. The outer membrane was easily released, leaving mureinoplasts, by mild desalting in a 20% sucrose solution containing 50 mM tris(hydroxymethyl)aminomethane-HCl buffer, pH 7.8. The membrane was recovered by treatment with DNase I and CsCl buoyant density centrifugation. Chemical analyses revealed that the outer membrane was mainly composed of 31% protein, about 20% extractable lipids (mainly phospholipids), and lipopolysaccharides. The proteins had about 18 mol % excess of acidic over basic amino acids. The phospholipids comprised phosphatidyl ethanolamine, phosphatidyl glycerol, cardiolipin, and an unidentified phospholipid containing glucose, which seemed mainly associated with the outer membrane. The content of lipopolysaccharides in the outer membrane was calculated arbitrarily as 30% from the heptose content. A unique feature of these lipopolysaccharides seemed to be higher lipid content than found in lipopolysaccharides of other gram-negative bacteria. The major fatty acids of bound lipids of the outer membrane resembled those of the lipopolysaccharides obtained from cell envelope preparation and contained high concentrations of 3-hydroxy lauric acid.

Amino Acids↗

PubMed1975

On the sugar content of the lipopolysaccharides of the various strains known as Yersinia enterocolitica.

With a single exception among 11 strains, each strain of Y. enterocolitica representing one of the six O-groups possesses, as judged by the sugar composition of its lipopolysaccharides, a particular chemotype. All 14 of the strains examined possessed glucosamine, KDO, two heptoses and glucose. In the most complicated chemotype 10 sugars were demonstrable. Of three Y. enterocolitica strains not included in the 6 O-groups, two had the same chemotype as the representatives of the O-groups IV and VI. Details can be seen in the two tables.

Animals↗

PubMedDate not supplied

[Characterization of lipopolysaccharides from Ralstonia solanacearum].

Lipopolysaccharides (LPSs) from four strains of Ralstonia solanacearum belonging to biovar I (ICMP 6524, 8115, 5712, and 8169) were isolated and investigated. The structural components of the LPS molecule, such as lipid A, the core oligosaccharide, and O-specific polysaccharide (O-PS), were obtained after mild acid hydrolysis of the LPS preparations. In lipid A from all the LPS samples studied, 3-hydroxyhexadecanoic, 2-hydroxyhexadecanoic, tetradecanoic, and hexadecanoic fatty acids prevailed. The dominant monosaccharides of the core oligosaccharides of all of the strains studied were rhamnose, glucose, glucosamine, 2-keto-3-deoxyoctulosonic acid, and heptose. However, individual strains varied in the content of galactose, ribose, xylose, and arabinose. Three types of the O-PS structure were established, which differed in their configuration (alpha or beta), as well as in the type of the bond between glucosamine and rhamnose residues (1-->2 or 1-->3).

Chromatography, Gas↗

PubMed1977

Core region in Proteus mirabilis lipopolysaccharide.

Four R mutants of P. mirabilis were isolated. The composition of their degraded polysaccharides (PS) obtained from the respective lipopolysaccharides (LPS) as well as the composition and properties of the PS-fractions separated by column chromatography were examined. The results were compared with those obtained with PS of the wild type. One of the mutants could be classified as an Ra-type mutant, presenting a complete LPS core. This polysaccharide core contains: galacturonic acid, glucosamine, glucose, D-glycero-D-mannoheptose, L-glycero-D-mannoheptose in a molar ratio of 1 : 1 : 1 : 1 : 2 and 2-keto-3-deoxyoctonate. Taking into consideration the common sugars described previously in the LPS chemotypes of P. hauseri, the composition of the complete core region mentioned above represents the LPS core part of all the chemotypes, containing two different heptoses.

Bacteriophage Typing↗

PubMed1995

Structural and serological characterization of Hafnia alvei lipopolysaccharide core region.

The structures and serological activities of core oligosaccharide of Hafnia alvei strains have been investigated. Methylation analysis, NMR spectroscopy and various specific degradation procedures were the principal methods used. It is concluded that, core hexasaccharides are identical in the lipopolysaccharides tested and are built of two glucose, three heptose and one 2-keto-3-deoxyoctulosonic acid residues. The antiserum raised against the ATCC13337 oligosaccharide core-tetanus toxoid conjugate cross-reacted strongly with all lipopolysaccharides used as antigens in ELISA test, suggesting that this core region is the common structure in the Hafnia genus.

Carbohydrate Sequence↗

PubMed1997

[Structure of repeating unit of the O-specific polysaccharide from Yersinia mollaretii strain WS 42/89].

The O-specific polysaccharide was isolated from Yersinia mollaretii strain WS 42/89 and characterized. Studies of the partial hydrolysis and methylation products and the 1H and 13C NMR spectroscopy data enabled the following structure to be proposed for the repeating unit of the polysaccharide: -->2)-beta-D-Galp-(1-->3)-alpha-D-6dGulp-(1--> The same structure was ascribed to the O-specific polysaccharide from Yersinia enterocolitica serovar O:6.31. The difference between these two O-antigens from various Yersinia species is in the absence of D-glycero-D-manno-heptose residues in the structure of the lipopolysaccharide from Y. mollaretii.

Heptoses↗

PubMed2000

Partially hydroxylated 2,5-disubstituted bis-tetrahydrofurans from carbohydrates

The diverse bioactivities of annonaceous acetogenins have recently attracted increasing interest. Many of these natural products contain one or more 2,5-disubstituted tetrahydrofuran rings as a core unit; these are important for the bioactivity, since it is believed that these anchor the compounds to the surface of the membrane. Therefore, the synthesis of functionalized bis-tetrahydrofurans is an important task and we have developed a synthetic pathway to all four diastereomeric, partially hydroxylated bis-tetrahydrofurans, that is, 3,6:7,10)-dianhydro-2,8,9-trideoxy-L-erythro-D-ido-undecitol (1), 3,6:7,10-dianhydro-2,8,9-trideoxy-D-threo-D-ido-undecitol (2), 3,6:7,10-dianhydro-2,8,9-trideoxy-L-threo-D-ido-undecitol (3), and 3,6:7,10-dianhydro-2,8,9-trideoxy-D-erythro-D-ido-undecitol (4) starting from D-glucose. The reaction of the aldose with Meldrum's acid led to the C-glycosidic 3,6-anhydro-1,4-lactone 6, which was converted to the aldehyde building block 2,5-anhydro-3,4,7-tri-O-benzyl-6-deoxy-aldehydo-D-ido-heptose (11). Chain elongation of 11 with the Grignard reagent derived from 1-bromo-3-butene gave the diastereomers 3,6-anhydro-1,4,5-tri-O-benzyl-2,8,9,10,11-pentadeoxy-L-glycero-D-ido-undec-10-enitol (12) and 3,6-anhydro-1,4,5-tri-O-benzyl-2,8,9,10,11-pentadeoxy-D-glycero-D-ido-undec-10-enitol (13). The relative threo configuration of the major product 12 was confirmed by X-ray structure analysis. Epoxidation and subsequent cyclization afforded the cis and trans diastereomers 19 and 20, respectively, in a 1:1 ratio. Subsequent cleavage of the protecting groups and separation of the isomers furnished the target compounds in good overall yields.

Journal Article↗

PubMed1986

Molecular requirement for interleukin 1 induction by lipopolysaccharide-stimulated human monocytes: involvement of the heptosyl-2-keto-3-deoxyoctulosonate region.

Experiments were undertaken to localize in the lipopolysaccharide (LPS) the minimal structural determinants sufficient to initiate the signal leading to interleukin 1 (IL 1) secretion by human monocytes. Our results clearly demonstrated that this signal is triggered by structures present in the so-called inner-core region which chemically consists of 2-keto-3-deoxy-D-manno-octulosonic acid (KDO) and heptose in many LPS of gram-negative bacteria. Thus, the isolated polysaccharide region of Bordetella pertussis endotoxin as well as fragments derived therefrom containing the reducing KDO unit were able to induce similar levels of IL1 induction as the native LPS. Similarly, the trisaccharide alpha-D-manno-heptopyranosyl-(1-3)-alpha-D-manno-heptopyranosyl -(1-5)-3 -deoxy-D-manno-octulosonic acid (hep-hep-KDO), representative for the inner-core region of a large number of enterobacterial LPS, was a very potent IL 1 inducer. Neither KDO monosaccharide, nor the alpha-(2-4)-linked 3-deoxy-D-manno-octulosonic acid disaccharide isolated from Salmonella rough-form LPS promoted the signal indicating that the minimal structure of endotoxin able to induce IL 1 secretion resides in the hep (1-5)-KDO disaccharide.

Carbohydrate Sequence↗

PubMed1998

Enhancement of sample loadings for the analysis of oligosaccharides isolated from Pseudomonas aeruginosa using transient isotachophoresis and capillary zone electrophoresis - electrospray - mass spectrometry.

The analysis of underivatized core oligosaccharides arising from mild acid hydrolysis of lipopolysaccharides from Pseudomonas aeruginosa serotype 05 was achieved using a transient isotachophoretic preconcentration method coupled to capillary zone electrophoresis-electrospray-mass spectrometry (tCITP-CZE-ES-MS). The combination of a tCITP preconcentration step provided a 10- to 50-fold enhancement of sample loading and a corresponding improvement in sensitivity compared to the conventional zone electrophoresis format. Electrophoretic conditions, enabling the separation of these anionic analytes, were developed to determine possible sites of heterogeneity on either the core or the O-chain structures. The tCITP-CZE-ES-MS technique provided unparalleled resolution of the different core glycoforms and oligosaccharides obtained from the acid cleavage of the native endotoxins whether isolated following conventional gel permeation chromatography or obtained from direct hydrolysis of the bacterial isolates. These investigations also highlighted the highly phosphorylated nature of these complex cell membrane components, where the heptose residues of the core oligosaccharide can bear up to six phosphate groups.

Carbohydrate Sequence↗

PubMed1991

Relationship between chemical composition and biological function of Pseudomonas aeruginosa lipopolysaccharide: effect on human neutrophil chemotaxis and oxidative burst.

There are conflicting data on the effect of bacterial lipopolysaccharides (LPS) on the function of human neutrophils. The present study was designed to examine the relationship between chemical composition and the modulatory effect of LPS on human neutrophil function. LPS was extracted from five strains of Pseudomonas aeruginosa isolated from cystic fibrosis patients by the hot phenol-water method. Chemical characterization included neutral sugars, amino components, and fatty acids. Neutrophils isolated from peripheral blood of healthy individuals were preincubated with different concentrations of LPS. After preincubation, the chemotaxis and chemiluminescence of neutrophils to various stimuli were determined. It was shown that LPS from different strains did not exert the same degree of regulatory effect on neutrophil functions. LPS from strain 174-O:9 exerted the most pronounced effect on neutrophil function seen as inhibition of neutrophil chemotaxis toward the chemotactic peptide f-Met-Leu-Phe and zymosan-activated serum (ZAS) and priming of the cells for less than or equal to 8-fold enhancement of chemiluminescence response to f-Met-Leu-Phe. Conversely, LPS from strain 1118-O:3 had no effect on neutrophil chemotaxis and a slight effect on chemiluminescence. The major differences in chemical composition of the LPS from these two strains are in the rhamnose and heptose content of the O side chain and in the alanine content of the core region. These data indicate that chemical composition of the LPS molecule may play an important role in biological activity of LPS.

Chemotaxis, Leukocyte↗

PubMed1989

Interaction between phage G13 and its oligosaccharide receptor studied by equilibrium dialysis.

The reversible binding of phage G13, a phi X174-like single-strand DNA phage, to a 3H-labelled nonasaccharide from the lipopolysaccharide of its natural host Escherichia coli C was studied with equilibrium dialysis. The binding constant (Ka) was determined to 1.3 x 10(7) M-1 in Scatchard and Lineweaver-Burk plots. Approximately one saccharide bound per G13 phage particle which suggests that only one of the 12 spikes in each G13 virion was engaged in the phage/receptor saccharide interaction. Equilibrium dialysis inhibition experiments with saccharides from lipopolysaccharides of an isogenic series of Salmonella typhimurium mutants showed that hepta- and pentasaccharides from two G13-sensitive bacteria, i.e., with efficiencies of plating of 0.1-1.0 compared to E. coli C, were efficient inhibitors with Ka-values greater than or equal to 1.2 x 10(7) M-1. The octa- and hexasaccharides from two G13 resistant strains, with efficiency of plating less than or equal to x 10(-4), were either greater than 1000-fold or greater than 15-fold less efficient as inhibitors with Ka-values less than or equal to 8.8 x 10(5) M-1. The results show that phage G13 binds in a specific and reversible way to penta-, hepta-, and nonasaccharides from G13 sensitive bacteria with the specificity residing in the hexose and heptose region of the core lipopolysaccharide.

Chemical Phenomena↗

PubMed1989

Definition of the phage G13 receptor as structural domains of trisaccharides in Salmonella and Escherichia coli core oligosaccharides.

The interaction between phage G13 and different bacterial and synthetic oligosaccharides has been studied using equilibrium dialysis inhibition. The results, and conformational analysis of the oligosaccharides, make us conclude that the phage G13 carbohydrate receptor is a conformational domain involving three sugar residues. The following trisaccharide elements contain the domain: alpha-D-Galp-(1----3)-[alpha-D-Galp-(1----6)]-alpha-D-Glcp, alpha-D-Manp-(1----3)-[alpha-D-Manp-(1----6)-alpha-D-Manp , and alpha-D-Glcp-(1----3)-[L-gly-alpha-D-man-Hepp-(1----7)]-L-gly-alph a-D- man-Hepp. Thus two structures, either a hexose substituted with alpha-D-glycopyranosyl groups in the 3- and 6-positions, or a heptose substituted with such groups in the 3- and 7-positions are functional G13 binding sites. Such domains are present in several cores of lipopolysaccharides from Salmonella and Escherichia coli species. Some cores, e.g. those from S. typhimurium chemotypes Ra, Rb1 and Rb2, contain two such domains. The identification of two G13 receptor domains within different core saccharides could explain the broad host range of this phage.

Carbohydrate Conformation↗