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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal antibody (mAb) probes were used to investigate the expression of lipopolysaccharide (LPS) on four Escherichia coli strains, grown under a variety of conditions in batch culture which mimicked some of the in vivo environmental conditions of an infected host. Techniques of silver staining, immunoblotting, whole cell ELISA and flow cytometry were all used to monitor the expression of LPS on the bacteria and the binding of the anti-LPS mAbs. Growth in heat-inactivated sheep serum and magnesium-depleted conditions demonstrated increased expression of LPS core and subsequent increased binding of anti-core mAbs. Magnesium-depleted conditions also resulted in decreased production of O-polysaccharide material. Iron-depleted bacteria showed only minor changes in LPS expression, although increased binding of anti-core mAbs was observed. Nitrogen-deficient/high-carbon conditions, chosen to promote capsule production, resulted in increased expression of O-polysaccharide and decreased binding of anti-core mAbs.
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PMID:Monoclonal antibodies as probes for detecting lipopolysaccharide expression on Escherichia coli from different growth conditions. 172 64

A comparative study on the endotoxic effects of lipopolysaccharide (LPS) from Veillonella parvula ATCC 10790 and from Bacteroides intermedius BMH was performed using an in vivo approach in the C57BL/6 mouse. Phenol-water extracted LPS of such anaerobes was purified by ultracentrifugation and DNase/RNase digestion, and characterized by a metachromatic assay for endotoxins and by electrophoresis on SDS-polyacrylamide gel and silver staining. Mouse LD50 for V. parvula LPS was 1.479 mg and for B. intermedius greater than 3.160 mg. Sublethal amounts of the LPS from anaerobes as well as from facultative aerobes decreased daily water intake and body weight in the mouse. Endotoxin from Salmonella typhimurium SL1102, Escherichia coli 0128:B12 and V. parvula had a strong effect on water intake and body weight, whereas Bacteroides intermedius LPS activity was very weak. The results of the present report suggest that V. parvula LPS has a toxic in vivo activity on mouse, which is comparable to LPS from classic enteric organisms and stronger than B. intermedius LPS.
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PMID:Biological effects of Veillonella parvula and Bacteroides intermedius lipopolysaccharides. 177 87

The optimal conditions for the analysis of the lipopolysaccharide (LPS) of two serotype A1 isolates and a serotype A2 isolate of Pasteurella haemolytica by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining were determined. The LPS of the A1 isolates possessed O side chains, consisting of high molecular mass bands with the appearance of a ladder-like pattern, as well as a low molecular mass core-oligosaccharide region; the LPS of the A2 isolate consisted only of the core-oligosaccharide region. Furthermore, the LPS of the two A1 isolates differed in the core-oligosaccharide region. Optimal resolution of low molecular mass LPS components was obtained in a 15% acrylamide resolving gel containing 4 M urea whereas optimal resolution of high molecular mass components was obtained when urea was omitted. Conventional silver staining resulted in excellent visualisation of LPS bands, whereas a modified staining method did not detect additional bands, as has been demonstrated with the LPS of Pseudomonas aeruginosa. Proteinase K digestion of outer membranes gave more clearly defined LPS profiles than did similar digestions of whole cells, and more closely resembled the profiles of purified LPS. With the exception of slight variation in the average molecular mass of a group of O side chains between logarithmic and stationary phases there were no differences in LPS profiles at various stages of the growth cycle; freezing and thawing of LPS samples had no effect on the profiles.
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PMID:Optimal conditions for the analysis of Pasteurella haemolytica lipopolysaccharide by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. 178 78

The adherence of lipopolysaccharides (LPSs) from periodontal disease-associated bacteria to saliva-coated hydroxyapatite (S-HA) and serum-coated HA beads was examined by chromogenic Limulus activity (toxicolor test). Phenol-water extracted LPS preparations from Bacteroides intermedius, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans, Eikenella corrodens, and rough-type LPS from Escherichia coli adhered to S-HA and serum-coated beads and agglutinated human erythrocytes. The adhered LPSs to S-HA and serum-coated HA beads were not removed by vigorous washing with distilled water. LPSs from Bacteroides (Porphyromonas) gingivalis strains and wild-type E. coli did not adhere to S-HA, serum-coated HA beads or show hemagglutinating activity. SDS-PAGE patterns stained with silver stain showed that LPSs adhered to S-HA, and serum-coated HA beads and erythrocytes possessed a distinct fast-migrating band similar to rough-type LPS. B. gingivalis LPSs possessed slow-migrating and repeating ladder bands similar to wild-type LPS.
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PMID:Adherence to experimental pellicle of rough-type lipopolysaccharides from subgingival plaque bacteria. 181 66

A rifampin-resistant mutant of Brucella abortus, designated RB51, was derived by repeated passage of strain 2308 on Trypticase soy supplemented with 1.5% agar and varying concentrations rifampin or penicillin. The RB51 colonies absorbed crystal violet and RB51 cell suspensions autoagglutinated, indicating a rough type colonial morphology for this strain. No O-chain component was detected in lipopolysaccharide (LPS) extracted from RB51 on SDS-PAGE gels stained with silver. Western blot analysis with the monoclonal antibody BRU 38, which is specific for the perosamine homopolymer O-chain of smooth Brucella LPS, indicated that the LPS of RB51 is highly deficient in O-chain when compared with the parenteral smooth strain 2308 or rough strain 45/20. Biochemically, RB51 resembles parental strain 2308 in its ability to utilize erythritol. Intraperitoneal inoculation of RB51 into mice results in a splenic colonization which is cleared within four weeks post infection. RB51 does not revert to smooth colony morphology upon passage in vivo (mice) or in vitro. Mice infected with RB51 produce antibodies against B. abortus antigens including class 2 and 3 outer membrane proteins but not against the O-chain. Furthermore, rabbits, goats and cattle hyperimmunized with sonicates of RB51 develop antibodies to B. abortus cellular antigens but do not develop antibodies specific for the O-chain. Immunization of mice with 1 x 10(8) viable RB51 organisms confers significant protection against challenge with virulent B. abortus strain 2308.
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PMID:Biological properties of RB51; a stable rough strain of Brucella abortus. 190 58

Most strains of Pseudomonas aeruginosa can express two chemically and immunologically distinct types of lipopolysaccharide (LPS), an antigenically conserved form called A band and the serotype-specific form called B band. To study the molecular controls regulating expression of the A-band LPS antigen, we have cloned the genes involved with A-band LPS expression. Strain AK1401, a phage-resistant mutant of PAO1 which was shown previously to produce only A-band LPS and not the O-antigen-containing B-band LPS, was mutagenized by using ethyl methanesulfonate to generate an A-band-deficient mutant called rd7513. A cosmid clone bank of P. aeruginosa PAO1 whole genomic DNA was constructed in Escherichia coli. The gene bank was mobilized en masse into strain rd7513, and detection of complementation of synthesis of A band was done by screening transconjugants in a colony immunoblot assay with the A-band-specific monoclonal antibody N1F10. One recombinant cosmid, pFV3, complemented synthesis of A-band polysaccharide in rd7513. Silver-stained polyacrylamide gel and Western immunoblot analyses of LPS extracted from the transconjugant rd7513(pFV3) showed that the A band produced had a higher molecular weight than the A band of AK1401. Analysis of the plasmid pFV3 showed that it contained a chromosomal insert of 27 kb. Two subclones of pFV3, namely, pFV35 and pFV36, containing chromosomal inserts of 5.3 and 4.2 kb, respectively, also complemented A-band expression in rd7513. The LPS banding profile of rd7513(pFV35) was similar to that of AK1401, while the LPS profile of rd7513(pFV36) more closely resembled that of rd7513(pFV3). pFV3 complemented A-band expression in five of the six P. aeruginosa O serotypes which lack A band as well as in rough strain AK44 but failed to complement A-band expression in core mutants AK1012 and AK1282, suggesting that pFV3 contains genes for A-band expression and that synthesis of a complete core region in isogenic mutant strains is required for A-band synthesis.
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PMID:Molecular cloning of genes involved with expression of A-band lipopolysaccharide, an antigenically conserved form, in Pseudomonas aeruginosa. 190 20

To elucidate the clinical significance of serum-sensitivity of respiratory pathogenic Pseudomonas aeruginosa (P. aeruginosa) strains, we examined serum-sensitivity of P. aeruginosa isolated from 16 patients with lower respiratory tract infections and clinical backgrounds of these patients. We also evaluated the virulence of four serum-resistant and four serum-sensitive P. aeruginosa strains in murine pneumonia model induced by intratracheal challenge, and the silver-stained profiles of purified lipopolysaccharide (LPS) from these strains. Serum-sensitive strains were isolated only from patients with chronic bronchitis, bronchiectasis, and diffuse panbronchiolitis colonized with P. aeruginosa, and rarely caused pneumonias, while serum-resistant strains caused pneumonias in some cases. Intratracheal challenge of mice with 5 x 10(7) cfu per mouse of a serum resistant strain caused fatal hemorrhagic pneumonia with bacteremia. In contrast, the same dose of a serum-sensitive strain provided non-fatal pneumonia without bacteremia. LD50 of serum-sensitive strains in a murine model of P. aeruginosa pneumonia were at least 2-10 times higher than those of serum-resistant strain. The LPS profiles of two serum-resistant strains and one serum-sensitive strain showed ladder-like patterns. The similar analysis demonstrated that one serum-sensitive strain was lack of ladder-like patterns. These data support that serum-sensitive P. aeruginosa strains are less virulent than serum-resistant P. aeruginosa strains in the lower respiratory tract, and serum sensitivity of P. aeruginosa strains is determined by the structure of the O-side chain of LPS; either lack of the O-side chain or the presence of sparse O-side chain.
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PMID:[Serum sensitivity of Pseudomonas aeruginosa isolated from sputum as a virulence factor in the lower respiratory tract]. 191 Jan 22

The viability of four strains of Bordetella bronchiseptica, two strains of B. pertussis and one strain of B. parapertussis exposed to hyperimmune and pre-colostrum porcine serum was examined. Viable cell numbers (cfu/ml) of the B. pertussis strains and a rough strain of B. bronchiseptica (CSU-P-1) decreased by 99% and 99.99%, respectively, after exposure for 1 h to porcine hyperimmune serum. In contrast, smooth B. bronchiseptica strains and the B. parapertussis strain showed no significant decrease in viable cell numbers after the same treatment. B. bronchiseptica strain CSU-P-1 also showed a 99% decrease in viable cell numbers after exposure to pre-colostrum porcine serum for 1 h whereas the other strains tested showed no decrease in viable numbers under the same conditions. Heating the hyperimmune and pre-colostrum serum at 56 degrees C for 30 min resulted in the loss of bactericidal activity suggesting the involvement of complement in both systems. Analysis of silver-stained SDS-PAGE profiles of lipopolysaccharide (LPS) extracted from the bacterial cells indicated that the smooth strains of B. bronchiseptica and the B. parapertussis strain possessed high mol. wt O-side chain-like material, whereas the B. pertussis strains and B. bronchiseptica strain CSU-P-1 did not. Gel filtration of acid-hydrolysed LPS samples indicated two distinct carbohydrate peaks for the strains with high mol. wt O-side chain-like material, whereas the other strains each yielded one distinct peak. Western-blot analysis indicated a positive reaction for anti-B. bronchiseptica antibodies to the high mol. wt O-side chain-like material of all serum-resistant strains used in this study.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serum sensitivity and lipopolysaccharide characteristics in Bordetella bronchiseptica, B. pertussis and B. parapertussis. 201 Sep 7

We recently cloned biosynthesis genes for the O7-lipopolysaccharide (O7-LPS) side chain from the Escherichia coli K-1 strain VW187 (M. A. Valvano, and J. H. Crosa, Infect. Immun. 57:937-943, 1989). To characterize the O7-LPS region, the recombinant cosmids pJHCV31 and pJHCV32 were mutagenized by transposon mutagenesis with Tn3HoHo1, which carries a promoterless lac operon and can therefore generate lacZ transcriptional fusions with target DNA sequences. Cells containing mutated plasmids were examined for their ability to react by coagglutination with O7 antiserum. The LPS pattern profiles of the insertion mutants were also investigated by electrophoresis of cell envelope fractions, followed by silver staining and immunoblotting analysis. These experiments identified three phenotypic classes of mutants and defined a region in the cloned DNA of about 14 kilobase pairs that is essential for O7-LPS expression. Analysis of beta-galactosidase production by cells carrying plasmids with transposon insertions indicated that transcription occurs in only one direction along the O7-LPS region. In vitro transcription-translation experiments revealed that the O7-LPS region encodes at least 16 polypeptides with molecular masses ranging from 20 to 48 kilodaltons. Also, the O7-LPS region in VW187 was mutagenized by homologous recombination with subsets of the cloned O7-LPS genes subcloned into a suicide plasmid vector. O7-LPS-deficient mutants of VW187 were complemented with pJHCV31 and pJHCV32, confirming that these cosmids contain genetic information that is essential for the expression of the O7 polysaccharide.
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PMID:Genetic analysis of the O7-polysaccharide biosynthesis region from the Escherichia coli O7:K1 strain VW187. 216 82

Fifty Escherichia coli strains belonging to nine classic EPEC (enteropathogenic E. coli) O:H serotypes from infantile diarrhea were examined for enzyme polymorphism and typed according to their multilocus genotypes. They were further examined for lipopolysaccharide (LPS) patterns by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver staining, for localized adhesion to HEp2 cells, and for their outer membrane protein (OMP) pattern. A very close relationship was detected among electrophoretic type, O:H serotype, biotype, LPS type, and OMP pattern. Most likely these characteristic EPEC groups (all type I) each represented bacterial clones, and furthermore they could be grouped into two genetically closely related clusters. In each cluster the only phenotypic character that differed among strains was the O antigen, which might suggest that the genetic background for the LPS side chains can be transferred horizontally among EPEC strains. The results support the idea that O:H serotyping is useful for studies of epidemiologic linkages between cases of EPEC diarrhea.
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PMID:Clonal relationships among classic enteropathogenic Escherichia coli (EPEC) belong to different O groups. 219 12


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