Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In an attempt to obtain pure and well characterized smooth lipopolysaccharide (S-LPS) and rough lipopolysaccharide (R-LPS), smooth and rough strains of Brucella abortus were extracted by two different modifications of the phenol-water method. S-LPS was obtained in the phenol phase, and R-LPS was obtained in the aqueous phase. Further purification was accomplished by treatment with enzymes, detergents, NaI as a chaotropic agent to separate non-covalently bound contaminants, and by gel filtration. The degree of purity of the molecules was determined by chemical and immunological analysis and by electrophoresis in sodium dodecyl sulfate-polyacrylamide gels. Lipid identification by gas-liquid chromatography showed seven major fatty acids. Palmitic acid accounts for about 50%, stearic acid accounts for about 10%, and hydroxylated fatty acids account for less than 5% of total fatty acids. 2-Keto-3-deoxyoctonate but not heptose was detected in the sugar analysis. Protein was found to be firmly bound to S-LPS but not to R-LPS.
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PMID:Purification and characterization of smooth and rough lipopolysaccharides from Brucella abortus. 10 57

The bacterial component responsible for the induction of transient cold agglutinin syndrome in rabbits after intravenous injection of heat-killed Listeria monocytogenes type 4B has been purified and biologically and chemically characterized. A purified immunoglobulin M cold agglutinin was prepared from high-titer sera resulting from the immunization of rabbits with heat-killed L. monocytogenes type 4B and was subsequently used to monitor the purification of the bacterial component responsible for its induction. The bacterial component was isolated from a hot phenol-water extract of lyophilized L. monocytogenes type 4B by multiple molecular sieve chromatography. Upon chemical analysis the purified material was found to be strikingly similar in chemical composition to gram-negative lipopolysaccharide endotoxins. The material contained 15% total fatty acid (of which 50% was beta-hydroxymyristic acid), 40 to 45% neutral sugar (glucose, galactose, and rhamnose), 11.5% amino sugar, 12% uronic acid, 2.5% 2-keto-3-deoxyoctonic acid, 2% heptose, 0.87% phosphorus, and 1.6% amino acid, thereby accounting for 85 to 90% of the weight of the component. Electron micrographs of the purified material were similar to those of lipopolysaccharide preparations from gram-negative organisms. The purified material exist in aqueous solutions as large aggregates, but can be dissociated into a single smaller subunit (3.1S) by dialysis against sodium dodecyl sulfate buffer. The listerial component was toxic and pyrogenic to rabbits, producing symptoms typical of gram-negative endotoxins. Activity in the limulus lysate gelation assay and in the carbocyanine dye assay provides a further link of this material with classical gram-negative endotoxins.
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PMID:Isolation, characterization, and biological properties of an endotoxin-like material from the gram-positive organism Listeria monocytogenes. 11 Jun 84

An antigenic complex has been isolated in a highly purified from from the Melvin strain of Neisseria gonorrhoeae. The complex has a molecular weight of 9.3 x 10(6) and on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was found to consist of several subunits; the most predominant had the following molecular weights: 110,000, 94,000, 68,000, a smear containing (52,000, 48,000, and 44,000), 42,000, 36,000, 29,000, 28,000, 26,000, and 12,000 comprising 89% of the total protein. With the exception of the subunit of molecular weight 110,000, no change in the content or the mobility of other subunits was observed when beta-mercaptoethanol was omitted from the denaturation solution of sodium dodecyl sulfate electrophoresis. Amino acid analysis of the complex showed a predominance of hydrophobic amino acids. These data implicated noncovalent interactions between the subunits. When the cells were labeled with fluorescamine it was possible to obtain a fluorescent complex with identical properties. Among several buffers used for the isolation of the complex, 0.2 M tris(hydroxymethyl)aminomethane buffer (pH 7.5) gave maximum yield with low amounts of lipopolysaccharide and phospholipid; the choice of the buffer for column chromatography did not seem to make any difference. The high protein content and low amounts of lipopolysaccharide and phospholipid are characteristic properties of the complex.
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PMID:Antigenic polypeptide complex from the Melvin strain of Neisseria gonorrhoeae: isolation and properties. 11 90

A number of polyacrylamide gel systems and solubilization procedures were studied to define the number and nature of "major" polypeptide bands in the outer membrane of Pseudomonas aeruginosa. It was shown that five of the eight major outer membrane proteins were "heat modifiable" in that their mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was determined by the solubilization temperature. Four of these heat-modifiable proteins had characteristics similar to protein II of the Escherichia coli outer membrane. Addition of lipopolysaccharide subsequent to solubilization caused reversal of the heat modification. The other heat-modifiable protein, the porin protein F, was unusually stable to sodium dodecyl sulfate. Long periods of boiling in sodium dodecyl sulfate were required to cause conversion to the heat-modified form. This was demonstrated both with outer membrane-associated and purified lipopolysaccharide-depleted protein F. Furthermore, lipopolysaccharide treatment had no effect on the mobility of heat-modified protein F. Thus it is concluded that protein F represents a new class of heat-modifiable protein. It was further demonstrated that the electrophoretic mobility of protein F was modified by 2-mercaptoethanol and that the 2-mercaptoethanol and heat modification of mobility were independent of one another. The optimal conditions for the examination of the outer membrane proteins of P. aeruginosa by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis are discussed.
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PMID:Outer membrane of Pseudomonas aeruginosa: heat- 2-mercaptoethanol-modifiable proteins. 11 60

The properties of different lipopolysaccharide (LPS) preparations to induce C3 conversion in human serum was studied by means of crossed immunoelectrophoresis. C3 conversion by the alternative pathway was evaluated after calcium depletion, and lipid A-dependent activation was measured by means of inhibition with polymyxin B sulfate. LPS from Bacteroides oralis converted Co mainly via the alternative pathway, whereas LPS from Fusobacterium nucleatum and Veillonella parvula const pronounced lipid A-dependent conversion. The results are discussed in relation to the chemical composition of the LPS preparations.
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PMID:Human complement activation by lipopolysaccharides from bacteroides oralis, fusobacterium nucleatum, and veillonella parvula. 12 Nov 8

Mouse spleen cells transformed by certain mitogens and subsequently fixed with glutaraldehyde can be utilized as stimulators in the mixed lymphocyte reaction. In addition to bacterial lipopolysaccharide which has been shown previously to be effective, we have found the other B cell mitogens, dextran sulfate and Concanavalin A-Sepharose, to be functional. The ability of the treated cells to activate allogeneic cells in MLR depends upon the concentration of glutaraldehyde and the type of tissue culture medium utilized.
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PMID:Factors affecting the stimulating capacity of mitogen-transformed, glutaraldehyde-treated mouse spleen cells in the mixed lymphocyte reaction. 14 88

As measured by [(3)H]thymidine uptake, spleen cells of mice injected 7 d previously with a single dose of cyclophosphamide (Cy) (125 mg x kg (-1)) gave an enhanced response to dextran sulfate (DS), a diminished response to lipopolysaccharide (LPS), and a normal response to concanavalin A. Addition of syngeneic thymocytes to spleen cells inhibited the enhanced response of the cells to DS and slightly enhanced their response to LPS. Pretreatment of thymocytes by 4-hydroxyperoxycyclophosphamide (4HP-Cy) in vitro (an in vitro active derivative of Cy) abrogated the effect of thymocytes on the DS response but not on the LPS response. Pretreatment of spleen cells by small doses of 4HP-Cy (0.1-1.0 mug. ml(-1)) in vitro enhanced the capacity of the cells to respond to DS but either did not affect, or even diminished their capacity to respond to LPS. The enhancement of the DS response by 4HP-Cy treatment could not be detected using spleen cells depleted of T cells or lacking functioning T cells. 4HP-Cy doses more than 3 mug ml(-1) diminished or abolished the capacity of the spleen cells to respond to LPS as well as their capacity to respond to DS. The results show (a) that in contrast to the LPS-reactive B-lymphocyte subset, the proliferative capacity of DS-reactive subset is negatively controlled by a Cy- and 4HP-Cy-sensitive T-cell subset and (b) that these T- suppressor cells are more sensitive to Cy and 4HP-Cy (to their respective active alkylating metabolites) than B lymphocytes and T cells carrying other immunological functions.
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PMID:T-suppressor cells sensitive to cyclophosphamide and to its in vitro active derivative 4-hydroperoxycyclophosphamide control the mitogenic response of murine splenic B cells to dextran sulfate. A direct proof for different sensitivities of lymphocyte subsets to cyclophosphamide. 15 40

The polymyxin antibiotics polymyxin B sulfate and colistin methane sulfonate were examined for their ability to inhibit responses to the polyclonal B-cell activators (PBA) bacterial lipopolysaccharide (LPS), dextran sulfate (DS), pneumococcal polysaccharide (SIII), and purified protein derivative of tuberculin (PPD) in spleen cell cultures. Polymyxin concentrations of 1 and 10 microng/ml significantly inhibited both the deoxyribonucleic acid synthetic and polyclonal antibody responses stimulated by LPS, DS, and SIII. At these concentrations of polymyxins, responses to PPD and to the T-cell mitogens concanavalin A and phytohemagglutinin were not affected. Inhibition was not caused by a generalized lymphocyte toxicity. After dialysis of LPS-polymyxin and DS-polymyxin mixtures, the PBA preparations showed decreased mitogenic activity. Thus, the polymyxins probably interacted directly with the LPS and DS molecules. The mitogenic response to DS was more significantly inhibited than the response to a nonsulfated dextran. The cationic property of the polymyxins probably allows attachment to negatively charged groups in the mitogenically relevant parts of some but not all PBA molecules,, this attachment resulting in the loss of PBA activity.
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PMID:Polymyxins as inhibitors of polyclonal B-cell activators in murine lymphocyte cultures. 19 87

The effects of endotoxin (lipopolysaccharide [LPS]) on the pathogenesis of canine endotoxin shock were compared with those of LPS which had interacted with polymyxin B sulfate prior to administration. Both LPS and polymyxin B-modified LPS caused comparable early decreases in aortic blood pressure, leukocyte and platelet numbers, and serum complement levels. However, in dogs receiving polymyxin B-modified LPS the late hypotensive phase was significantly ameliorated and lethality was significantly decreased. These data indicate that polymyxin B-modified LPS, though significantly less lethal than unmodified LPS, was capable of major interactions with several components of the humoral defense system, and support the concept that such interactions are not determinative in the pathogenesis of canine endotoxin shock.
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PMID:Polymyxin B sulfate modification of bacterial endotoxin: effects on the development of endotoxin shock in dogs. 22 76

Human peripheral blood phagocytes ingest Escherichia coli 026:B6 lipopolysaccharide (LPS)-coated paraffin oil droplets containing Oil red O only if fresh serum deposits C3 on the surfaces of the particles (opsonizes them), by reactions involving the properdin system. The rate of binding of purified [125-I]C3 in serum to LPS-coated particles correlated precisely with the rate of acquisition of ingestibility assayed spectrophotometrically. Once opsonized, LPS-coated particles remained fully ingestible and retained fixed [125-I]C3 radioactivity even after exposure to extremes of temperature, pH, ionic strength, phospholipases, urea or guanidine, some nonionic and ionic detergents, and organic solvents. Trypsin, human conglutinogen-activating factor, another heat-stable activity found in human serum, and sodium dodecyl sulfate removed radioactivity and diminished ingestibility of the opsonized particles. Alkylation, reduction plus alkylation and F(ab')2 from anti-C3 blocked ingestibility but did not alter particle-bound radioactivitymelectrophoretic and tryptic peptide autoradiographic analysis of dodecyl sulfate eluates of opsonized particles, cleansed of many contaminating proteins by boiling with 2 M NaCl (yet still opsonized), revealed that the polypeptide with C3-derived radioactivity had a mol wt of approximately 140,000 and was composed of 70,000 mol wt subunits linked by disulfide bonds. Immunochemical analysis and comparison of the peptide structure of the eluate with that of C3 indicated that the opsonic fragment is not the fragment defined as C3b but a smaller derivative of C3.
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PMID:The opsonic fragment of the third component of human complement (C3). 23 57


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