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PubMed1981

Purification and further characterization of phenol extract from Listeria monocytogenes.

A phenol-water extract of Listeria monocytogenes virulent strains 9-125 (serotype 4b) was purified by 3 cycles of ultracentrifugation. The purified extract reacted positively in Limulus amoebocyte lysate assay at a concentration of 1 microgram/ml. This value was 1,000 times higher than that for Salmonella abortus equi lipopolysaccharide. The phenol extract was toxic to chicken embryos (median lethal dose was 40.5 micrograms) and contained carbohydrates (heptose, hexose, hexosamine, methylpentose, 2-keto-3-deoxyoctanate, dideoxyhexose), lipid, 16 amino acids in the protein moiety, glucosamine, galactosamine, phosphorus, and ribonucleic acid.

Amino Acids↗

PubMed1981

Isolation of a nontoxic lipid A fraction containing tumor regression activity.

Galanos-type endotoxin obtained from the heptose-less mutant of Salmonella typhimurium was converted to Lipid A by two cycles of treatment with sodium acetate, pH 4.5, at 100 degrees and separated on a DEAE-cellulose column into several fractions (Fractions III to VII). Tumor regression studies with strain 2 guinea pigs and syngeneic line 10 hepatocellular carcinoma showed that all fractions were effective when combined with trehalose dimycolates and an additional tumor regression factor (previously designated ACP) and incorporated into oil droplets (78 to 100% cures). A low polar fraction (Fraction IV) was relatively nontoxic [the medium lethal dose for 11-day-old chick embryos inoculated i.v. (CELD50) was more than 10 micrograms] and nonpyrogenic [the dose estimated to give a fever index (area under fever curve) of 40 sq cm in rabbits when 1 hr and 1 degrees are plotted as 1 (FI40) was 5 micrograms] as compared to the unfractionated Lipid A (CELD50 of 0.0546 micrograms; FI40 of 0.046 micrograms). All other fractions were toxic and pyrogenic and caused severe endotoxic shocks when combined with N-acetylmuramyl-L-seryl-D-isoglutamine and injected i.v. into guinea pigs. Fraction IV plus N-acetylmuramyl-L-seryl-D-isoglutamine did not cause endotoxic shock. The phosphate content of Fraction IV was about one-half of that detected in the toxic fractions.

Acetylmuramyl-Alanyl-Isoglutamine↗

PubMed1981

Isolation of adenosine 5'-diphosphate-D-glycero-D-mannoheptose. An intermediate in lipopolysaccharide biosynthesis of Shigella sonnei.

From a Shigella sonnei R mutant which incorporates into its cell wall lipopolysaccharide D-glycero-D-mannoheptose and contains no L-glycero-D-mannoheptose, a nucleotide-linked sugar was isolated and identified as adenosine 5'-diphosphate-D-glycero-d-mannoheptose by chemical and chromatographic analysis. This intermediary compound is assumed to play a role in heptose biosynthesis of Enterobacteria.

Adenosine Diphosphate Sugars↗

PubMed1981

Presence and location of an O-acetyl group in O4-antigen of Vibrio parahaemolyticus.

A polysaccharide moiety (PS) released from O4-LPS of Vibrio parahaemolyticus was purified. The constituent sugars of the purified PS were glucose, galactose, arabinose, fucose, heptose, N-acetyl galactosamine and an unknown N-acetyl amino sugar. The unknown amino sugar was deduced to be a terminal deoxy amino sugar from its NMR spectrum. PNMR spectroscopy at 200 MHz, periodate oxidation and treatment with alpha-L-fucosidase of the purified PS sample before and after alcoholic sodium methoxide-treatment suggested that PS contained an O-acetyl and alpha-linked non-reducing terminal L-fucose and that the O-acetyl group was located at the C-2 or C-4 position of the non-reducing terminal fucose. The contribution of the O-acetyl group located in L-fucose to the O4-antigenic determinant seemed to be small, judging from immunochemical experiments.

Acetylation↗

PubMed1995

Chemical structures of the core region of Campylobacter jejuni O:3 lipopolysaccharide and an associated polysaccharide.

The complete structure for the core oligosaccharide region of the water-insoluble low-M(r) lipopolysaccharide of Campylobacter jejuni serotype O:3 from phenol/water extraction of bacterial cells was assigned through studies on derivatives of the liberated oligosaccharide. Structure determinations were performed using 1H-NMR and 31P-NMR spectroscopies, methylation analysis supported by fast-atom-bombardment mass spectrometry, and Smith degradation experiments. It was concluded that the complete chains in the core oligosaccharide had the following structure in which a proportion of the terminal residues were phosphorylated: [formula: see text] From a similar series of experiments, it was concluded that an associated polysaccharide, which was isolated from the water phase of the phenol/water extracts, had the following repeating unit in which a proportion of the previously unknown L-glycero-D-ido-heptose (L-alpha-D-ido-Hep) residues were present as 3-hydroxypropanoyl esters, and were not covalently linked to the lipopolysaccharide: [formula see: text]

Campylobacter jejuni↗

PubMed1975

[Chemical and serological characterization of Salmonella lipopolysaccharides from different phases of growth (author's transl)].

Chemical and serological investigations were carried out on lipopolysaccharides of 4 Salmonella S-forms and of 1 SR-mutant, extracted from bacteria at different ages of culture (early exponential to stationary growth phase). The results show that the fatty acid composition of Lipid A (lauric-, myristic-, palmitic-, and beta-hydroxy-myristic acids) does not undergo any significant change during the growth of the cultures. However, there are differences in the molar ratios of the fatty acids from strain to strain. In all phases of growth Lipid A is substituted by basaloligosaccharide, to the same extent, as can be seen from the constant ratios of beta-hydroxy-myristic acid: heptose. Serological experiments (haemagglutination inhibition tests, absorption of antibodies by LPS-coated erythrocytes) showed that in no case the basaloligosaccharide is completely substituted by O-specific chains and that basaloligosaccharide exhibits free R-antigen structures which are mainly of chemotypes Ra, Rb and Rc, for the SR-mutant only of types Ra and Rb. There is no demonstrable dependence upon the phases of growth. In the O-specific polysaccharide chains the sugars of the main chain and the side bound dideoxy sugars (abequose and tyvelose) show a constant 1:1 molar ratio in all phases. In the case of S. typhimurium, antigen factors 1, 4 and 12(2), the biosynthesis of which is controlled by modifying oaf genes and/or by a lysogenic phage, are of a somewhat weaker expression in the exponential phase than in the latter phases of growth. In the SR-mutant, lipopolysaccarides with (low) serological O1 and O12(2) activity are only extractable by the phenol/water method, but not by the PCP method. In three out of four S-forms, changes occur in the length of the O-specific polysaccharide chains, whereas the number of repeating units of the fourth strain remains almost unchanged. The lipopolysaccharides of the SR-mutant contain in all phases of growth about one repeating unit. In all strains the covering of the cell surface by lipopolysaccharide molecules changes during the course of growth, as can be seen by comparing the relative cell surface and the content of Lipid A fatty acids of the bacteria. Lipid A synthesis in the 4 S-forms is reduced in the exponential phase and/or in the phase of delayed growth acceleration. The extent of biosynthesis of the carbohydrate moiety of lipopolysaccharides is independent of that of Lipoid A. In the SR-mutant, Lipoid A and Polysaccharide are formed in increased amounts in the exponential growth phase.

Cell Wall↗

PubMed1993

Association of plasmids with the carbohydrate composition of the O-antigen in Shigella dysenteriae type 1.

Six different prepared mutant strains of Shigella dysenteriae type 1 with various combinations of 'core' plasmids of 140, 6, and 2 Mdal, were cultivated separately and their lipopolysaccharide (LPS) samples were isolated, which on delipidation afforded polysaccharides and oligosaccharides. The LPS and prepared O-antigen polysaccharides were subjected to acid hydrolysis, and the constituent sugars were analysed by paper chromatography and gas liquid chromatography (GLC), using CP Sil 8 CB fused silica capillary column equipped with a flame ionization detector. The mutant strains, harbouring the 6 Mdal plasmid, contained rhamnose, galactose, and N-acetyl glucosamine in their O-antigen polysaccharides with a minor variation in the relative proportions of these sugar constituents as compared to those of the control strain. The sugar composition of the O-antigen polysaccharides prepared from the mutant stains, without the 6 Mdal plasmid but containing 2 or 140 Mdal plasmid, contained galactose and N-acetyl glucosamine but no rhamnose. However, mutant strains with none of the core plasmids contained traces of rhamnose and were devoid of N-acetyl glucosamine, but contained heptose. These results suggest that 6 Mdal plasmid is essentially required for the complete synthesis of O-antigen polysaccharides. However, the 140 and 2 Mdal plasmids might also have an association with synthesis of carbohydrate composition of the O-antigen in S. dysenteriae type 1.

Carbohydrates↗

PubMed1994

Lipooligosaccharide biosynthesis in pathogenic Neisseria. Cloning, identification, and characterization of the phosphoglucomutase gene.

The lipooligosaccharide (LOS) of pathogenic Neisseria is an important factor in disease pathogenesis. Little is known about the genes involved in neisserial LOS biosynthesis. To elucidate specific LOS biosynthetic genes, we screened a Tn916 library that was constructed in Neisseria meningitidis strain NMB. This strain expresses a single LOS that has an molecular mass of 4.5 kDa and binds monoclonal antibody (mAb) 3F11. This library was screened using a mAb panel that recognizes structural differences in neisserial LOS oligosaccharides. A stable LOS mutant of strain NMB was identified which we designated NMB-R6. This mutant expressed an LOS with an molecular mass of approximately 3.1-3.2 kDa and did not bind mAb 3F11. Genomic DNA from this mutant transformed N. meningitidis strain NMB to the tetracycline resistant NMB-R6 phenotype greater than 10(-4)/recipient/micrograms of DNA. In addition, we transformed Neisseria gonorrhoeae strain 1291 (LOS phenotype molecular mass 4.5 kDa, mAb 3F11+) to the NMB-R6 LOS phenotype with N. meningitidis NMB-R6 genomic DNA. Analysis of N. gonorrhoeae strain 1291-R6 LOS by mass spectroscopy showed that the LOS oligosaccharide structure is GlcNAc-->Hep2phosphoethanolamine-->2-keto-3-deoxymannooctuloson ic acid (where Hep is heptose). Sequence analysis showed that the transposon is inserted into the 3' end of a gene that has homology to the human phosphoglucomutase (PGM) gene. Sequence comparison indicated that the putative PGM gene in N. gonorrhoeae 1291 and N. meningitidis NMB had 92% identity at the DNA level. PGM and glucokinase activity was present in cell free extracts of N. meningitidis NMB and N. gonorrhoeae strain 1291. N. meningitidis NMB-R6 and N. gonorrhoeae strain 1291-R6 had no detectable PGM activity, whereas glucokinase activity was similar to the wild type strains. PGM activity can be reconstituted in N. meningitidis strain NMB-R6 by transformation with the cloned PGM gene. SDS-polyacrylamide gel electrophoresis demonstrated that NMB-R6 transformed with the PGM gene expressed the 3F11+, 4.5-kDa LOS of the parent NMB strain. The inability of N. meningitidis NMB-R6 and N. gonorrhoeae strain 1291-R6 to convert glucose 6-phosphate to glucose 1-phosphate results in the truncated LOS phenotype expressed by these mutants.

Amino Acid Sequence↗

PubMed1993

An antigenic polysaccharide from Campylobacter coli serotype O:30. Structure of a teichoic acid-like antigenic polysaccharide associated with the lipopolysaccharide.

A water-soluble antigenic polysaccharide of high M(r) associated with the lipopolysaccharide has been isolated from phenol-water extraction of cells of Campylobacter coli serotype O:30. The polysaccharide and oligosaccharide degradation products formed on O-dephosphorylation and by periodate oxidation followed by reduction have been investigated by one- and two-dimensional 1H, 13C, and 31P NMR. It is concluded that the antigenic polysaccharide has a teichoic acid-like structure with a poly-Ribitol phosphate, [5-Ribitol-1-P]n, backbone with side chains at O-2 of O-(6-deoxy-beta-D-talo-heptopyranosyl)-(1-->4)-(2-acetylamino-2-deoxy-beta-D- glucopyranosyl) units. The structure is unusual in Gram-negative bacteria and is unique in possessing 6-deoxy-D-talo-heptose as a constituent sugar. Evidence for the relationship of the antigenic polysaccharide to the lipopolysaccharide of low M(r) is discussed.

Campylobacter coli↗

PubMed1995

The lipopolysaccharide of Legionella pneumophila serogroup 1 (strain Philadelphia 1): chemical structure and biological significance.

The lipopolysaccharide (LPS, endotoxin) of Legionella pneumophila serogroup 1 (Philadelphia 1) exhibits peculiar chemical features which may account for its importance as a bacterial virulence factor. The O-chain of this LPS constitutes a homopolymer of an unusual sugar, 5-acetamidino-7-acetamido-8-O-acetyl-3,5,7, 9-tetradeoxy-D-glycero-L-galacto-nonulosonic acid (legionaminic acid) of which about 10-75 residues are present. Due to the lack of free hydroxyl groups, this homopolymer renders the cell surface highly hydrophobic and, therefore, supports adherence to the membrane of target cells including alveolar macrophages. Investigations of the serological specificity of the serogroup 1 LPS revealed a monoclonal antibody (mAb 3/1) which recognizes an epitope located in the environment of the 8-O-acetyl group of legionaminic acid. According to epidemiological studies, this determinant appears to be associated with L. pneumophila virulence. The outer core oligosaccharide of L. pneumophila LPS exhibits also hydrophobic properties due to the presence of N- and O-acetyl groups as well as 6-deoxy sugars. The inner core expresses both similarities and differences as compared to enterobacterial core oligosaccharides in containing Kdo but lacking heptose and phosphate groups. Lipid A possesses some unique structural features since its backbone consists of a bisphosphorylated beta-GlcpN3N-(1-->6)-GlcpN3N disaccharide with only amide-linked acyl groups having 14-22 carbon atoms. Long chain fatty acids [28:0(27-oxo) and 27:0-dioic] possessing the double length as enterobacterial acyl groups, may be responsible for the low endotoxicity of L. pneumophila lipid A.

Animals↗

PubMed1996

Lipopolysaccharide biosynthesis in Rhizobium leguminosarum. Novel enzymes that process precursors containing 3-deoxy-D-manno-octulosonic acid.

The lipopolysaccharide of Rhizobium leguminosarum differs from that of other Gram-negative organisms. R. leguminosarum lipid A lacks phosphate groups, but it contains a galacturonic acid residue at the 4'-position and an aminogluconate moiety in place of the usual glucosamine 1-phosphate unit. R. leguminosarum lipid A is esterified with a peculiar long chain fatty acid, 27-hydroxyoctacosanoate, not found in enteric Gram-negative bacteria, and the inner core of R. leguminosarum contains mannose and galactose in place of heptose. Despite these differences, the biosynthesis of R. leguminosarum lipid A is initiated by the same seven enzyme pathway as in Escherichia coli (Raetz, C. R. H. (1993) J. Bacteriol. 175, 5745-5753) to form the phosphorylated precursor, (Kdo)2-lipid IVA, which is then processed differently. We now describe several novel Rhizobium-specific enzymes that recognize and modify (Kdo)2-lipid IVA. The 1- and 4'-phosphatases were detected using (Kdo)2-[1-32P]-lipid IVA and (Kdo)2-[4'-32P]-lipid IVA, respectively, as shown by release of 32Pi. In the presence of GDP-mannose and/or UDP-galactose, membranes of R. leguminosarum first transferred mannose and then galactose to (Kdo)2-[4'-32P]-lipid IVA. In addition, at least two hydrophobic metabolites were generated from (Kdo)2-[4'-32P]-lipid IVA in a manner that was dependent upon both membranes and a cytosolic factor from R. leguminosarum. These compounds are attributed to novel acylations of (Kdo)2-[4'-32P]-lipid IVA. E. coli membranes and cytosol did not catalyze any of the unique reactions detected in R. leguminosarum extracts. Our findings establish the conservation and versatility of (Kdo)2-lipid IVA as a lipid A precursor in bacteria.

Acyltransferases↗

PubMed1997

Characterization of O-antigens from different strains of Pseudomonas syringae pv. tabaci.

O-Antigens (lipopolysaccharides, LPS) were isolated by NaCl extraction from microbial biomass of Pseudomonas syringae pv. tabaci and purified by ultracentrifugation. Individual structural components of the LPS macromolecule (O-specific polysaccharide (O-PS), core oligosaccharide, and lipid A) were obtained and characterized. Fatty acids 3-OH-C10:0, C12:0, 2-OH-C12:0, 3-OH-C12:0, C16:1, C16:0, C18:1, and C18:0 were identified in the lipid A composition. Glucosamine, ethanolamine, and phosphoethanolamine were found in the hydrophilic part of the lipid A macromolecule in all strains tested. Lipid A preparations contained phosphorus and amino acids. Rhamnose, glucose, glucosamine, 2-keto-3-deoxyoctulosonic acid, heptose, alanine, and phosphorus were identified as the main core components. The strains differed in O-PS structure. We describe the O-chain of LPS in strain P-28. It contains repeating units of the following structure: [formula: see text] The O-PS structures of LPS from strains P-28 and 225 are identical, however, they differ substantially from that of strain 223. Both structures from strains 223 and 225 were reported previously. Antibodies to antigenic epitopes of O-PS, core, and lipid A were revealed in O-serum against the whole bacterial cells. Correlation of O-PS structure with the serological grouping of strains was observed.

Carbohydrate Conformation↗

PubMed1997

Immunochemical characterization of lipopolysaccharide from glucose-nonfermenting gram-negative clinical bacterial isolate.

A glucose-nonfermenting Gram-negative bacterial strain isolated from bronchofiberoscope used for examination of the patients suffering from pulmonary diseases was subjected to phenol-water extraction. Lipopolysaccharides (LPS) isolated from the water and the phenol phase differed in fatty acid composition. Both contained xylose, glucose, glucosamine and components typical for LPS, namely heptose, 3-deoxyoctulosonic acid (Kdo) and 3-hydroxymyristic acid. The presence of sphingosine in all LPS preparations classifies the strain to the genus Sphingomonas.

Animals↗

PubMedDate not supplied

[The chemical composition and biological activity of the glyco polymers in Ralstonia solanacearum (Yabuchi et al., 1995)].

Lipopolysaccharide and extracellular glyco polymers were isolated from cells of phytopathogenic bacteria Ralstonia solanacearum. It was established that the O-specific polysaccharides are characterized by a linear structure, composed of tetrasaccharide repeating units containing three L-rhamnose residues and one of N-acetylglucosamine residue. Core oligosaccharide along with typical monosaccharides such as rhamnose, glucose, heptose, KDO and glucosamine included fucose, galactose and arabinose. Serological activity of lipopolysaccharide is due to both O-specific polysaccharide and lipid A component. Extracellular glyco polymers contained both neutral (GP 1) and charged (GP 2 and GP 3) components. Rhamnose and glucose (GP 1, GP 2) or galactose (GP 3) were predominant monosaccharides, GP 2 displayed a high phytotoxic action in respect to tomato plants.

Amino Acids↗

PubMed1964