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)

The structure of the 4-amino-L-arabinose-lacking lipopolysaccharide of the Proteus mirabilis Rc-type mutant R4, derived from wild-type O28, was elucidated. The lipopolysaccharide core structure has previously been partially characterized. The linkage between heptose and deoxyoctulosonic acid(dOclA) is now reported, as well as the structure of the lipid A moiety of this mutant strain. Besides the tentative identification of an alpha-linked glucosamine disaccharide in the lipid A backbone accompanying the usual beta 1----6-linked glucosamine-disaccharide, the only significant structural variation to previous studies was the lack of substitution of the C-4' phosphate by 4-amino-L-arabinose. In addition, the substitution at C-8 of one dOclA unit by 4-amino-L-arabinose, previously reported for the R45 mutant of P. mirabilis 1959, is lacking in this R mutant. Also in addition to previous findings, the terminal unit of heptose was found to be substituted at C-7 with phosphorylethanolamine (PEtN) and not only with phosphate, although this substitution is not complete as demonstrated by the relevant signals in 31P-NMR. Additional studies with the wild-type strain P. mirabilis O28 revealed the presence of 4-amino-L-arabinose in both the core and the lipid A regions suggesting that the R4 mutant is defective in the biosynthesis of this amino sugar rather than in its transfer. Otherwise the lipid A regions of the mutant and the wild-type strain show no structural differences. The following formula is proposed for the lipopolysaccharide of 4-amino-L-arabinose-lacking mutant R4/O28 P. mirabilis: (Formula; see text)
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PMID:Structural studies on the core and lipid A region of a 4-amino-L-arabinose-lacking Rc-type mutant of Proteus mirabilis. 328 Mar 11

The role of intestinal flora in the production of anorexigenic substance was investigated. Proteus mirabilis (P. mirabilis) and Escherichia coli (E. coli) were found to produce an anorexigenic substance, while Enterococcus faecalis (E. faecalis, type 1 and 2) and Staphylococcus intermedius (S. intermedius) did not. The anorexigenic substance was purified and was detected as, a single though broad band by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The specific activity of the final form of the purified substance was 120 units/mg carbohydrate. The substance contained no protein residue and appeared to be a lipopolysaccharide. The evidence that intestinal flora produces an anorexigenic substance leads to an interesting assumption that the intestinal flora may be responsible for regulating food intake.
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PMID:The production of anorexigenic substances by intestinal flora. 329 69

The complete structure of the 0-specific polysaccharide of the strain Proteus mirabilis S 1959, as analyzed by 13C NMR, is presented. Some data demonstrating the significant heterogeneity of the 0-specific chain in the investigated lipopolysaccharide are also described.
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PMID:Structure of the 0-specific polysaccharide of Proteus mirabilis S 1959. 332 44

We described previously (W.M. Shafer, L.E. Martin, and J.K. Spitznagel, Infect. Immun. 45:29-35, 1984) the presence of a 37-kilodalton cationic antimicrobial protein (37K CAP) in extracts of granules prepared from human polymorphonuclear granulocytes (PMN). In this investigation, we prepared 37K CAP from PMN granule extracts by sequential ion-exchange and molecular-sieve chromatography and examined its antimicrobial activity against a number of gram-negative and gram-positive bacteria. At concentrations of 5 micrograms/ml or lower, 37K CAP exerted selective antimicrobial activity against gram-negative bacteria. These bacteria included Acinetobacter lwoffii, Escherichia coli, Neisseria gonorrhoeae, Pseudomonas aeruginosa, Pseudomonas cepacia, Salmonella typhi, Salmonella typhimurium, and Shigella sonnei. However, at 5 micrograms of 37K CAP per ml, Proteus mirabilis, Proteus vulgaris, and Serratia marcescens resisted this antimicrobial activity. The bactericidal activity of 37K CAP was greatest in acidic (pH 5.5) as opposed to alkaline (pH 7.5) media. The level of S. typhimurium resistance to 37K CAP correlated with the presence of O antigen in the lipopolysaccharide. In the absence of O antigen repeat units, resistance was proportional to the length of the core oligosaccharide. These results suggest that 37K CAP may contribute significantly to the ability of PMN to kill gram-negative bacteria by nonoxidative means, particularly as the maturing phagolysosome becomes acidified.
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PMID:Late intraphagosomal hydrogen ion concentration favors the in vitro antimicrobial capacity of a 37-kilodalton cationic granule protein of human neutrophil granulocytes. 352 87

The effect of Bacteroides asaccharolyticus on the opsonisation and phagocytosis of gram-positive and gram-negative bacteria by human polymorphonuclear leukocytes (PMNL) was investigated. Uptake of most isolates of staphylococci, streptococci and clostridia by PMNL after opsonisation with serum treated with B. asaccharolyticus was largely unimpaired. The same treatment of serum before opsonisation of isolates of Pseudomonas, Enterobacter, Klebsiella and Gardnerella resulted in the uptake by PMNL varying with individual isolates; a large reduction occurred with some and none with others. Treatment of serum with B. fragilis lipopolysaccharide before opsonisation of Proteus mirabilis produced a marked reduction in uptake, whereas treatment with B. fragilis capsular polysaccharide had little effect.
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PMID:Effects of Bacteroides asaccharolyticus cells and B. fragilis surface components on serum opsonisation and phagocytosis. 353 73

Phage P1C(-), in a state of the phage not infective to Escherichia coli K12, was able to form plaques on a wild-type strain of E. coli C and on Shigella sonnei in the presence of Mg2+. Citrobacter freundii, Enterobacter aerogenes, and a Salmonella typhimurium galE mutant were not lysed by, but were lysogenized with P1cinC(-), whereas Klebsiella pneumoniae, Proteus rettgeri, and S. typhimurium LT2 were not susceptible to either P1cinC(-) or P1cinC(+). The lipopolysaccharide structure of E. coli C and Sh. sonnei is discussed with reference to receptors for P1cinC(-) and P1cinC(+).
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PMID:Magnesium-dependent plaque formation by bacteriophage P1cinC(-) on Escherichia coli C and Shigella sonnei. 353 35

Escherichia coli subjected to cold osmotic shock released 30 to 40% of their fatty acid esters and 42% of their cellular hexosamine. In contrast, Enterobacter, although they released 40% of fatty acid esters, release only 25% of hexosamine. Proteus released less than 15% of either fatty acid esters or hexosamine. These differences are taken to explain the differences among the Enterobacteriaceae in releasing surface enzymes after osmotic shock. It is felt that the release of additional lipopolysaccharide after osmotic shock is necessary for the release of surface enzymes that are not freed by ethylenediaminetetraacetic acid-tris(hydroxymethyl)aminomethane exposure.
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PMID:Relation of lipopolysaccharide and fatty acid ester release to the ethylenediaminetetraacetic acid alteration of permeability in enterobacteriaceae. 498 63

Two proteins with apparent molecular weights of 39,000 and 36,000 (M(r) 39,000 and M(r) 36,000, respectively) were isolated from the outer membrane of Proteus mirabilis 19. M(r) 36,000 was shown to be free of detectable amounts of the M(r) 39,000 protein by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and free of lipopolysaccharide according to gas chromatographic analyses of 3-hydroxymyristic acid content. The M(r) 39,000 protein contained no detectable amount of lipopolysaccharide and only a trace of M(r) 36,000. Both isolated proteins gave strong reactions in antisera produced to purified P. mirabilis 19 cell walls (outer membrane proteins in the native state). This suggested that the proteins isolated by our methods essentially retained their native configuration upon resolubilization. Antisera produced in rabbits to the isolated proteins showed strongest reactions with the homologous antigen, but some cross-reactions with the heterologous protein and with P. mirabilis 19 lipopolysaccharide were observed. These cross-reactions could be attributed to specific responses to traces of the heterologous (contaminant) proteins present in the purified proteins used as immunizing antigens. The M(r) 39,000 and M(r) 36,000 proteins have no major antigenic determinants in common. Reactions with P. mirabilis 19 lipopolysaccharide in antisera to the outer membrane proteins could be completely removed by absorption of the antisera with the M(r) 36,000 protein.
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PMID:Immunological characterization of two major proteins isolated from the outer membrane of Proteus mirabilis. 615 31

Antibody-producing cell responses of mice to a protein isolated from the outer membrane of Proteus mirabilis were typical of the responses to a thymus-dependent antigen. The immunoglobulin G antibody-producing cell responses to the protein were increased after administration of the antigen complexed with either lipopolysaccharide or with vesicles of phospholipids extracted from P. mirabilis. The protein in turn significantly increased the immune response to lipopolysaccharide and also converted this response from predominantly immunoglobulin M to predominantly immunoglobulin G.
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PMID:Antibody-producing cell responses to an isolated outer membrane protein and to complexes of this antigen with lipopolysaccharide or with vesicles of phospholipids from Proteus mirabilis. 616 51

Chemically and serologically identical O-specific fractions were isolated from two different lipopolysaccharide (LPS) preparations of Proteus mirabilis O27. The release of a labile constituent in mild hydrolysis deprived those fractions of their serological activity. The compound was identified as N-acetyl-D-glucosamine and its terminal position in the molecule was established by methylation analysis. The non-carbohydrate constituent of the specific fractions: lysine and alanine are linked via their amino group. Terminal residues of N-acetylglucosamine, have to be considered as immunodeterminants of Proteus mirabilis O27. The role of other carbohydrate and non-carbohydrate constituents for the serological specificity of P. mirabilis O27 is discussed.
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PMID:Immunochemical studies on the O-specific side chains of the heterogeneous lipopolysaccharide from Proteus mirabilis O27. 618 57


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