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

The lipopolysaccharide (LPS) O-antigen side chains of Klebsiella serotype O1 have been studied by using mutants selected by resistance to a Klebsiella bacteriophage designated O1-A. Two classes of LPS mutants were identified. The major group (90%) synthesized rough LPS. The remaining 10% of the mutants produced a novel LPS profile that lacked the highest-molecular-weight O-substituted molecules (HMW-LPS) but still produced lower-molecular-weight O-substituted species (LMW-LPS). By using antisera raised against mutant Klebsiella strains and antiserum specific for Pasteurella haemolytica serotype 4, it was demonstrated that HMW-LPS and LMW-LPS contain shared epitopes. HMW-LPS also contained an epitope absent in LMW-LPS. This unique epitope was recognized by a monoclonal antibody (O1-52.6) and appears to be responsible for the serological cross-reaction between the O antigens of Klebsiella O1 and Escherichia coli O19. This HMW-LPS epitope was present in eight other Klebsiella O1 isolates which were examined. Electron microscopy demonstrated that HMW-LPS excluded overlying capsular polysaccharide for a distance of 25 to 40 nm. The distance was reduced to 10 to 18 nm in strains which synthesized only LMW-LPS and to zero in rough LPS strains. The HMW-LPS of Klebsiella O1 was shown to be an important virulence determinant, since this molecule was responsible for the resistance of the bacterium to nonspecific, complement-mediated serum killing.
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PMID:A high-molecular-weight fraction of smooth lipopolysaccharide in Klebsiella serotype O1:K20 contains a unique O-antigen epitope and determines resistance to nonspecific serum killing. 247 78

Coliphage K30 lysates contain free and phage-associated forms of a bacteriophage-encoded capsule depolymerase (glycanase) enzyme, active against the serotype K30 capsular polysaccharide of Escherichia coli. The free glycanase has been purified to apparent homogeneity. The molecular weight of the enzyme was estimated at 450,000, and when heated in SDS at 100 degrees C, the enzyme dissociated into two subunits of 90,000 and 52,000. The glycanase enzyme was used as a reagent to reversibly degrade the capsular layers on cells of Escherichia coli O9:K30 and Klebsiella O1:K20. This treatment rendered these bacteria sensitive to their respective lipopolysaccharide-specific bacteriophages, coliphage O9-1 and Klebsiella phage O1-3. This novel approach facilitated isolation of lipopolysaccharide O antigen side chain deficient mutants which retained the ability to synthesize the capsule. The response of defined mutants, O+:K-, O-:K+, and O-:K-, to exposure to nonimmune rabbit serum was measured. Results showed that the primary barrier against complement-mediated serum killing in both Escherichia coli O9:K30 and Klebsiella O1:K20 was the O antigen side chains of the lipopolysaccharide molecules. In both strains, the capsule played no role in the determination of serum resistance.
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PMID:Use of a bacteriophage-encoded glycanase enzyme in the generation of lipopolysaccharide O side chain deficient mutants of Escherichia coli O9:K30 and Klebsiella O1:K20: role of O and K antigens in resistance to complement-mediated serum killing. 248 25

Intradermal palpable MBT-2 tumor responded with bacterial lipopolysaccharide to hemorrhagic necrosis (LPS) in C3H/HeN (endotoxin sensitive) mice. We have tested LPS fractions isolated from E. coli, Klebsiella pneumoniae, Salmonella minnesota, Pseudomonas aeruginosa and Serratia culture filtrates. All these LPS preparations showed tumor necrotizing activity accompanied by toxicity (body weight loss) in C3H/HeN mice. However, MBT-2 tumors grown in an endotoxin-resistant strain (C3H/HeJ) of mice did not respond to LPS, even at a very high dose. In vitro, the LPS showed no cytotoxic effect on MBT-2 cells. For comparison, systemic administration of tumor necrosis factor (cachexin ) did not affect the i.d. tumor growth. These data indicate that host reactions to LPS (endotoxicity) plays a pivotal role in the expression of tumor necrosis. Accordingly, comparisons of tumor response between endotoxin sensitive and resistant mice avoid potential overestimation of the therapeutic value of certain bacterial products and/or LPS contaminated agents.
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PMID:Effect of bacterial lipopolysaccharide on growth of murine bladder cancer, MBT-2. 251 Mar 88

Monoclonal antibodies to Bordetella pertussis filamentous hemagglutinin (FHA) and lipopolysaccharide (LPS) were used in a colony blot enzyme-linked immunosorbent assay designed for rapid detection of B. pertussis. Bacterial colonies from Bordet-Gengou agar plates were blotted onto nitrocellulose filter disks, lysed by immersion in chloroform, and reacted with monoclonal antibodies. Following reaction with peroxidase-conjugated rabbit anti-mouse immunoglobulin antisera and 4-chloro-1-naphthol, blue dots representing single colonies appeared on the filters. Blotting of single B. pertussis colonies could be performed after incubation for 40 h, i.e., before the colonies were visible by eye on the agar surface. Ten of ten B. pertussis strains showed positive blotting reactions with antibodies specific for B. pertussis FHA and LPS. Fourteen of fourteen B. parapertussis strains reacted with two of the FHA-specific antibodies but not with two of the LPS-specific antibodies. Strains of B. bronchiseptica showed a variable reaction pattern. No cross-reactions were observed with strains of Streptococcus mitis, S. pyogenes, S. pneumoniae, Staphylococcus aureus, Branhamella catarrhalis, or Klebsiella pneumoniae. This assay may be useful for identification of B. pertussis and B. parapertussis in suspected cases of whooping cough.
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PMID:Rapid detection of Bordetella pertussis by a monoclonal antibody-based colony blot assay. 254 57

RU 41740 is a glycoprotein extract from Klebsiella pneumoniae described as a macromolecular aggregation of a lipopolysaccharide (LPS)-associated protein (F1 fraction) and a glycoproteic complex (P1 fraction). The human polymorphonuclear (PMN) response was studied after incubation of the cells in the presence of RU 41740, F1 and P1 fractions, or F1-P1 complex. Oxidative metabolism was assessed by chemiluminescence, O2 consumption, O2- generation, and degranulation by beta-glucuronidase release. Results were compared to data obtained with a homologous LPS. RU 41740, F1 fraction, and F1-P1 complex increased the respiratory burst of PMNs stimulated by opsonized zymosan (OZ). N-formylmethionylleucylphenylalanine (fMLP), phorbol myristate acetate, or the calcium ionophore A23187. The beta-glucuronidase release was stimulated by the same compounds when OZ or fMLP were used as stimuli. These effects were dose-dependent. In contrast, P1 fraction was inactive. Addition of polymyxin B resulted in a profound inhibition of both the F1 fraction and LPS activities but only in a partial inhibition of RU 41740 effects. These results strengthen the hypothesis that different biochemical pathways are involved in the enhancement of stimulated neutrophil functions by RU 41740.
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PMID:Comparative effects of F1 and P1 fractions obtained from a Klebsiella pneumoniae glycoproteic extract (RU 41740) on polymorphonuclear leukocytes. 255 90

It was previously reported that Klebsiella O3 lipopolysaccharide (LPS) exhibits extraordinarily strong adjuvant activity in augmenting antibody response against protein antigens in mice compared with other kinds of LPS, for example, LPS from Escherichia coli O55, O111, and O127 and Salmonella enteritidis. The present study was undertaken to clarify the relationship between the strong adjuvant activity in augmenting antibody response against deaggregated bovine gammaglobulin and the chemical structure of LPS. Among LPS from Klebsiella O1, O4, O5, and O7, only O5 LPS exhibited nearly the same degree of the strong adjuvant activity as did O3 LPS. The adjuvant activity of the other LPS was very weak in a degree similar to that of LPS from E. coli O55 and O127. Even when the natural forms of Klebsiella O3 LPS and O1 LPS were converted to various defined uniform salt forms, their adjuvant activity did not significantly differ from that of the respective natural forms. It is therefore unlikely that the difference in strength of the adjuvant activity between Klebsiella O3 LPS and O1 LPS is due to the difference in their salt forms. The common feature in the structures of Klebsiella O3 LPS and O5 LPS is their O-specific polysaccharide chains consisting of the mannose homopolysaccharides (mannans). LPS from E. coli O8 and O9, the O-specific polysaccharide chains of which consist of the mannans, also exhibited much stronger adjuvant activity than do LPS from E. coli O55 and O127, and the strength of the adjuvant activities of the former two was comparable to that of LPS from Klebsiella O3 and O5. On the other hand, LPS from Klebsiella O3 and O5 and E. coli O8 and O9 showed the ability to activate B lymphocytes polyclonally in vivo in a degree similar to that of the other kinds of LPS. From the present results it can be concluded that LPS possessing the O-specific polysaccharide moieties consisting of the mannans exhibit extraordinarily strong adjuvant activity in augmenting antibody response against protein antigen.
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PMID:Potent adjuvant action of lipopolysaccharides possessing the O-specific polysaccharide moieties consisting of mannans in antibody response against protein antigen. 257 97

Previously it was demonstrated that Klebsiella pneumoniae O3 lipopolysaccharide (KO3 LPS) exhibited much stronger adjuvant action on antibody response to subcutaneously (s.c.) injected sheep red blood cells or deaggregated bovine serum albumin than did other kinds of LPS, the R-form LPS lacking the O-specific polysaccharide chain of KO3 LPS (R-LPS), and the lipid A fractionated from KO3 LPS. We compared histological changes in the regional subcutaneous tissues of mice injected subcutaneously (s.c.) with KO3 LPS, the lipid A, and R-LPS. At the early stage after injection, KO3 LPS induced the infiltration of a large number of inflammatory cells, mainly polymorphonuclear leukocytes (PMN), at the site of injection. Neither R-LPS nor the lipid A induced the accumulation of PMN so much as KO3 LPS did. When injected s.c. with LPS from Escherichia coli O111 (EO111 LPS) and O55 (EO55 LPS), and Salmonella enteritidis (Sent LPS), the appearance of PMN at the regional site was much less than KO3 LPS. KO3 LPS could accumulate more 51Cr-labeled leukocytes at the injection site than EO111 LPS and Sent LPS. Administration of acetylsalicylic acid, which can inhibit leukocyte migration in inflammatory lesions, suppressed its adjuvant action. It was therefore suggested that the strong adjuvant action of KO3 LPS in s.c. injection might be dependent on its potent capability of accumulating PMN at the regional subcutaneous tissue. Furthermore, at the late stage after injection, the formation of several lymphoid follicles at the regional site was seen only in mice injected with KO3 LPS. It might be also related to the strong adjuvant action of KO3 LPS.
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PMID:A possible correlation between histological changes in regional subcutaneous tissue induced by bacterial lipopolysaccharides and their adjuvant activities. 258 46

Klebsiella pneumoniae mutants were obtained after UV irradiation and negative selection with anticapsular serum. Unencapsulation, rather than expression of a structurally altered capsule, was found in the mutants. The mutant strains showed no alterations in their outer membrane proteins and lipopolysaccharide, and a great similarity with the wild type in the properties tested (serum resistance, antimicrobial sensitivity, and lipopolysaccharide-specific bacteriophage sensitivity), with the exception of a higher cell surface hydrophobicity and resistance to bacteriophage FC3-9.
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PMID:Isolation and characterization of Klebsiella pneumoniae unencapsulated mutants. 264 25

Murine monoclonal antibodies that bind outer membrane antigens of the J5 mutant of Escherichia coli O111:B4 were derived from spleen cells of BALB/c mice immunized with killed whole cells and boosted with lipopolysaccharide (LPS) and LPS-associated proteins. Seven hybridomas were selected for their reactivity against the J5 LPS; they cross-reacted with O111, O55, O127, and O128 E. coli LPS. One (B7B3) also reacted with the Serratia marcescens LPS and Klebsiella pneumoniae lipid A. A protective effect was obtained with D6B4 antibody in a lethal endotoxemia model induced by LPS from O111, O127, and O128 E. coli serotypes in D-galactosamine-sensitized mice. D6B4 and D6B3 antibodies protected mice infected with E. coli O111:B4, when administered before infection. The D6B4 antibody was also protective when administered after infection. The antibodies D6B3 and D4B5 were protective in heterologous infection induced by E. coli O2:K1.
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PMID:Protective effects of murine monoclonal antibodies in experimental septicemia: E. coli antibodies protect against different serotypes of E. coli. 264 60

Lipopolysaccharide (10 micrograms/mL) derived from Klebsiella pneumoniae was injected into the middle ear of guinea pigs. The animals were killed painlessly on days 1, 3, and 7 after inoculation, and the mucosal samples from two sites within the tympanic cavity, close to the tympanic orifice and distal to the orifice, were examined for ciliary activity and epithelial morphology. At day 1 and day 3 serous effusion was observed and deterioration of ciliary activity and morphologic changes were observed. No effusion was recognized at day 7, when the ciliary activity in the distal mucosa was still diminished and that in the proximal mucosa had recovered to a normal level. Our data have shown that lipopolysaccharide extracted from K pneumoniae can produce otitis media with effusion in laboratory animals, and dysfunction of cilia due to lipopolysaccharide probably is responsible for the accumulation of middle ear effusion. The mucociliary system is indeed an important defense system and failure of such a system, especially in the mucosa close to the tympanic orifice, can cause the buildup of effusions.
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PMID:Mucociliary disease of the middle ear during experimental otitis media with effusion induced by bacterial endotoxin. 265 18


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