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

Log-phase cells of Serratia marcescens cultured at 30 degrees C were approximately 10-fold more hemolytic than those grown at 37 degrees C. By using a cloned gene fusion of the promoter-proximal part of the hemolysin gene (shlA) to the Escherichia coli alkaline phosphatase gene (phoA), hemolysin gene expression as a function of alkaline phosphatase activity was measured at 30 and 37 degrees C. No difference in alkaline phosphatase activity was observed as a function of growth temperature, although more hemolysin was detectable immunologically in whole-cell extracts of cells grown at 30 degrees C. The influence of temperature was, however, growth phase dependent, because the hemolytic activities of cells cultured to early log phase at 30 and 37 degrees C were comparable. Given the outer membrane location of the hemolysin, lipopolysaccharide (LPS) was examined as a candidate for mediating the temperature effect on hemolytic activity. Silver staining of LPS in polyacrylamide gels revealed a shift towards shorter O-antigen molecules at 37 degrees C relative to 30 degrees C. Moreover, there was less binding of O-antigen-specific bacteriophage to S. marcescens with increasing growth temperature, a finding consistent with temperature-mediated changes in LPS structure. Smooth strains of S. marcescens were 20- to 30-fold more hemolytic than rough derivatives, a result confirming that changes in LPS structure can influence hemolytic activity. The alkaline phosphatase activity of rough strains harboring the shlA-phoA fusion was threefold lower than that of smooth strains harboring the fusion plasmids, a result consistent with a decrease in hemolysin gene expression in rough strains. The absence of a similar effect of temperature on gene expression may be related to less-marked changes in LPS structure as a function of temperature compared with a smooth-to-rough mutational change.
 ...
PMID:Influence of growth temperature and lipopolysaccharide on hemolytic activity of Serratia marcescens. 305 45

The Pseudomonas aeruginosa polyvalent vaccine PEV and its 16 constituent monovalent extracts from International Antigenic Typing System serotypes 1 through 13 and 15 through 17 (J. J. Miler, J. F. Spilsbury, R. J. Jones, E. A. Roe, and E. J. L. Lowbury, J. Med. Microbiol. 10:19-27, 1977) were subjected to biochemical analysis and to detailed immunochemical analysis with rabbit anti-PEV immunoglobulins. The results of chemical analysis, of analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis performed in conjunction with silver staining, and of analysis by crossed immunoelectrophoresis, sodium dodecyl sulfate-polyacrylamide gel-crossed immunoelectrophoresis, and Western blotting showed clearly that lipopolysaccharide was a major constituent of each monovalent extract and that it was probably the dominant antigen present in at least 15 of the 16 monovalent extracts. A 16.2-kilodalton protein, which was pronase resistant and nonsedimentable at 105,000 X g and which appeared to be biochemically and antigenically unrelated to pili, was a common although minor antigen for all extracts. Several other proteins, some of outer membrane origin, were also detected in unformalinized extracts, but these were also minor antigenic constituents of the vaccine. Neither pilin nor flagellin appeared to be major protein constituents of tested monovalent extracts, although anti-flagella antibodies could be demonstrated in rabbit anti-PEV by Western blotting. Preliminary analysis by crossed immunoelectrophoresis of serum raised in volunteers to PEV also indicated the presence therein of antibodies to lipopolysaccharide antigens.
 ...
PMID:Immunochemical and biochemical analysis of the polyvalent Pseudomonas aeruginosa vaccine PEV. 308 Mar 73

The nature of the protective antigen in one of the sixteen monovalent extracts (viz., extract-6) contributing to the pseudomonas polyvalent extract vaccine (PEV) was studied in a mouse challenge assay. Selective removal, by filtration through Sep-Pak C18 cartridges, of two major protein antigens with molecular weights of 16,200 and 21,000 had no effect on the protection afforded by extract-6. When analyzed on the basis of 2-keto-3-deoxyoctonate, lipopolysaccharide (LPS) purified by hot phenol extraction (LPS-A) from Pseudomonas aeruginosa (International Antigenic Typing System serotype 6) could account in full for the protective capacity of extract-6. Comparative analysis of LPS heterogeneity by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver staining indicated that both extract-6 and LPS-A possessed similar spectra of smooth LPS molecules, containing between 10 and approximately equal to 50 O-antigen repeating units. Differences in the profiles of heterogeneity displayed by LPS in LPS-A and extract-6 were restricted to molecular species with short O-antigen chains. Subfractionation of LPS molecules on the basis of number of O-antigen repeating units was achieved by gel filtration in the presence of deoxycholate. Protection experiments performed on the subfractionated species of LPS-A revealed a relationship between O-antigen chain length and protective capacity; molecules with over 18 O-antigen repeating units being 50 to 100 times more protective than those with zero-two repeating units. The results indicate that most of the protection afforded by LPS-A and extract-6 can be accounted for by LPS molecules possessing extended (10 or more) O-antigen repeating units.
 ...
PMID:Smooth lipopolysaccharide is the major protective antigen for mice in the surface extract from IATS serotype 6 contributing to the polyvalent Pseudomonas aeruginosa vaccine PEV. 308 62

On SDS-PAGE, solubilized and proteinase K treated preparations of Neisseria gonorrhoeae strain BS4 (agar) showed differences in silver stained lipopolysaccharide (LPS) patterns, before and after induction to resistance to serum killing by incubation for 3 h at 37 degrees C with low Mr fractions from lysates of guinea pig red blood cells. Preparations from the original serum susceptible gonococci and LPS purified from such bacteria showed two components, but the preparations from the serum resistant gonococci were deficient in the higher Mr component. Furthermore, on immunoblotting with fresh human serum (FHS), the two LPS components of the susceptible gonococci reacted strongly with IgM. With preparations from the serum resistant gonococci there was no reaction in the area corresponding to the higher Mr component and a weaker reaction with the component of low Mr. Purified LPS from the susceptible gonococci neutralized the bactericidal activity of FHS against N. gonorrhoeae strain BS4 (agar) probably by reacting with the relevant antibody, since heated FHS was no longer bactericidal when mixed with a source of complement (human placental serum) after prior reaction with the LPS. These neutralization tests coupled with the results of immunoblotting strongly suggest that increased serum resistance is due to the lack of the high Mr LPS moiety.
 ...
PMID:Lipopolysaccharide alteration is associated with induced resistance of Neisseria gonorrhoeae to killing by human serum. 309 92

Lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) was excreted by Pseudomonas aeruginosa PAC1R during the late logarithmic growth phase. Characterization of cell-free culture supernatants by sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of significant amounts of lipopolysaccharide, part of which seemed to be tightly bound to lipase. After concentration of culture supernatants by ultrafiltration, lipase-lipopolysaccharide complexes were dissociated by treatment with EDTA-Tris buffer and subsequent sonication in the presence of the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. The solubilized lipase was purified by isoelectric focusing in an agarose gel containing the same detergent; the lipase activity appeared in a single peak corresponding to a distinct band in the silver-stained gel. The isoelectric point was 5.8. Analysis of purified lipase by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and scanning revealed an apparent molecular weight of 29,000 and a specific activity of 760 mu kat/mg of protein. Estimations based on these data showed that a single P. aeruginosa cell excreted about 200 molecules of lipase, each having a molecular activity of 2.2 X 10(4) per s.
 ...
PMID:Purification of extracellular lipase from Pseudomonas aeruginosa. 309 67

Analyses of chemical composition in whole cells of Rickettsia tsutsugamushi were performed and compared with those of the other rickettsiae and gram-negative bacteria. The results indicated that R. tsutsugamushi does not contain detectable amounts of 3-deoxy-D-mannooctulosonic acid, heptose, muramic acid, or glucosamine (less than 2, less than 2, less than 3, and less than 3 nmol/mg, respectively). The microorganism was found to contain four kinds of fatty acids (16:0, 18:0, 18:1, and 18:2), but not hydroxy fatty acids. Furthermore, in analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by silver or Coomassie blue staining, lipopolysaccharide bands were not detected in preparations treated with proteinase K. It is concluded that R. tsutsugamushi has little or no peptidoglycan or lipopolysaccharide.
 ...
PMID:Deficiency of peptidoglycan and lipopolysaccharide components in Rickettsia tsutsugamushi. 311 50

A gonococcal gene bank maintained in Escherichia coli K-12 was screened by colony immunoblotting, and a transformant expressing a surface antigen reactive to anti-gonococcal outer membrane antiserum was isolated. The isolate carried a recombinant plasmid, pTME6, consisting of approximately 9 kilobases of Neisseria gonorrhoeae DNA inserted into the BamHI site of pBR322. Surface labeling of E. coli HB101(pTME6) confirmed that the antigen was expressed on the E. coli cell surface. The antigenic material was resistant to proteinase K digestion and sensitive to periodate oxidation, indicating that the material was carbohydrate. Purified lipopolysaccharide (LPS) from HB101(pTME6) produced a unique band on silver-stained polyacrylamide gels that contained immunoreactive material as seen on Western blots of LPS samples. Only two of three E. coli LPS mutant strains carrying pTME6 reacted with the antigonococcal antiserum, suggesting that a certain E. coli core structure is necessary for antigen expression. We conclude that pTME6 contains one or more gonococcal genes encoding an LPS core biosynthetic enzyme(s) which can modify E. coli core LPS to produce a gonococcuslike epitope(s).
 ...
PMID:Expression of a cloned lipopolysaccharide antigen from Neisseria gonorrhoeae on the surface of Escherichia coli K-12. 311 95

Over five years 18 strains of Legionella pneumophila serogroup 6 were isolated in Amsterdam from the hot water supply in three hospitals and from one patient. Immunodiffusion and immunoblot procedures showed that these strains were identical. Profiles of isolated lipopolysaccharides from the 18 strains and the reference serogroup 6 strain were visualised in polyacrylamide gels stained with silver. Four strains from hospital A, isolated in 1982, 1984, and 1985 displayed similar lipopolysaccharide profiles which were different in relative mobility from those of hospitals B and C. Those from hospital B (12 strains isolated in 1983 and 1986) and C (one strain) were similar in relative mobility but different in colour. The strain from a patient with acquired immune deficiency syndrome (AIDS) in hospital A displayed a lipopolysaccharide profile characteristic of hospital A. These reproducible profiles were all different in relative mobility from the reference serogroup 6 strain. They can be used as a marker system in epidemiological surveys of serologically identical serogroup 6 strains. Lipopolysaccharide patterns from strains isolated throughout the years in the same hospital were similar. This suggests an outgrowth from organisms inhabiting the plumbing system rather than reseeding from the Amsterdam mains supply.
 ...
PMID:Differences in lipopolysaccharide profiles of serologically identical Legionella pneumophila serogroup 6 strains. 313 16

EDTA and EGTA when used in conjunction with AgNO3 enhanced the antibacterial action of the latter significantly, so that strains of Klebsiella pneumoniae and Staphylococcus aureus resistant to 70 micrograms/ml of AgNO3 were observed to became sensitive to 10 micrograms/ml of this compound. The synergistic effect of EDTA appears to be due to a mechanism other than the removal of lipopolysaccharide from outer membrane, as its effect could be observed in even non-LPS containing gram positive S. aureus cells. Penicillamine, another potent chelator had an opposite effect so that it decreased the toxicity of silver ions.
 ...
PMID:Effect of certain chelating agents on the antibacterial action of silver nitrate. 314 59

Recently evidence has been obtained that a minute amount of cytidine 5'-monophospho-N-acetyl neuraminic acid (CMP-NANA) or a closely related compound is the low Mr factor in human red blood cells which induces Neisseria gonorrhoeae (BS4(agar] to resistance to killing by fresh human serum. Induction of gonococci to resistance by both CMP-NANA and semi-purified low Mr factor from red blood cells was accompanied by a 35-55% reduction of silver staining of lipopolysaccharide separated in SDS-PAGE gels of proteinase K digests. These alterations in lipopolysaccharide are probably responsible for conferring serum resistance. However, lipopolysaccharide-containing digests from resistant as well as from susceptible gonococci neutralised serum bactericidal activity. These observations may have wider implications since CMP-NANA is a sialylating agent wide-spread in mammalian tissues and LPS is ubiquitous amongst Gram-negative pathogens.
 ...
PMID:Cytidine 5'-monophospho-N-acetyl neuraminic acid and a low molecular weight factor from human blood cells induce lipopolysaccharide alteration in gonococci when conferring resistance to killing by human serum. 314 16


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>