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At least 19 recordsLinked to original sources
PubMed1979

The structure of lipopolysaccharide from an Escherichia coli heptose-less mutant. III. Two fatty acyl amidases from Dictyostelium discoideum and their action on lipopolysaccharide derivatives.

Two fatty acyl amidases have been partially purified from the slime mold, Dictyostelium discoideum. Their action on lipopolysaccharide derivatives, especially Compound I, has been studied. Amidase I removes specifically the beta-hydroxymyristyl group, which is present on the amino group adjacent to the C-1 phosphate. The product, Compound V, is then a substrate for Amidase II, which removes the remaining beta-hydroxymyristyl group from the amino group in the distal glucosamine ring to give Compound VI. Compound I itself is resistant to Amidase II. Thus, the two enzymes show a high degree of structural specificity. The structure of lipopolysaccharide from the E. coli K-12 mutant is concluded in the light of studies reported in this and the accompanying papers, and this structure is discussed in relation to other bacterial lipopolysaccharides.

Amidohydrolases↗
PubMed1975

[Growth and lipopolysaccharide content of salmonellae grown in submersed cultures according to the batch-method. 2. Communication: influence of growth phases on lipopolysaccharide synthesis (author's transl)].

The paper describes cultivations of 4 Salmonella S-forms and 1 SR mutant, performed in complex medium under constant conditions of temperature, pH and aeration. The experiments show that lipopolysaccharide (LPS) biosynthesis underlies quantitative differences with the growth phases, resulting in changes in the LPS content of the cell masses. During the exponential phase a decline takes place in the percentage of LPS contained by the 4 S-forms. In addition, in the phase of delayed growth acceleration, 3 of these strains exhibit temporary, complete stagnation in LPS formation. When the cultures enter the stationary phase, LPS biosynthesis also discontinues. The SR-mutant differs from the S-forms especially in that the rate of LPS synthesis and with it, the percent lipopolysaccharide content of the cells, increase greatly in the exponential growth phase. The causes and effects of the changes observed are discussed.

Cell Division↗
PubMed1979

Ultrastructural localisation of lipopolysaccharide-binding sites with peroxidase-conjugated lipopolysaccharides.

The localisation of lipopolysaccharide-binding sites on erythrocytes with peroxidase-coupled LPS is described. LPS was isolated from Fusobacterium nucleatum (Fus MC-8) by phenol-water extraction. The LPS was coupled to horseradish peroxidase by the two-step method of Avrameas and Ternynck (1971). The biological and serological activities of the conjugated LPS were compared with those of the native material. Peroxidase could be coupled to LPS without significant loss of endotoxic or serological activity. The LPS-peroxidase conjugate could be demonstrated on erythrocytes by light and electron microscopy.

Animals↗
PubMed1976

New sugars from antigenic lipopolysaccharides of bacteria: identification and synthesis of 3-O-[(R)-1-carboxyethyl]-L-rhamnose, an acidic component of Shigella dysenteriae type 5 lipopolysaccharide.

A new acidic sugar, 3-O-[(R)-1-carboxyethyl]-L-rhamnose (1), has been identified as a constituent of the O-antigenic lipopolysaccharide of Sh. dysenteriae type 5. The structure of 1 has been established by physico-chemical methods and by synthesis. Alkylation of methyl 2,5-di-O-benzyl-alpha-L-rhamnofuranoside (6) with (S)- or (R)-2-chloropropionic acids, followed by removal of the protecting groups, afforded 3-O-[(R)-1-carboxyethyl]-L-rhamnose (9) and 3-O-[(S)-1-carboxyethyl]-L-rhamnose (10), respectively. The properties of 1 coincide with those of 9.

Antigens, Bacterial↗
PubMed1978

Macrophage stimulation by bacterial lipopolysaccharides. II. Evidence for differentiation signals delivered by lipid A and by a protein rich fraction of lipopolysaccharides.

Stimulation of macrophages to lyse tumor cells is a property common to lipopolysaccharide (LPS) extracted from a variety of smooth and rough bacterial strains by several different preparative procedures. The relationship between macrophage stimulation and the structural characteristics of LPS is defined. In protein-free LPS, lipid A bears the stimulatory signal which results in the differentiation of elicited macrophages into killer cells. The polysaccharide moiety is neither stimulatory itself nor does it block the activity of complete LPS on macrophages. Extraction of LPS by the butanol or Boivin procedures produces preparations in which LPS is complexed through its lipid A moiety to a protein rich component, LAP. Isolated LAP delivers a macrophage differentiation signal which is independent of lipid A. The presence of these two structurally distinct constituents in the cell walls of gram-negative bacteria broadens the biological environments in which they can stimulate macrophages in vivo.

Cell Differentiation↗
PubMed1979

Bacterial lipopolysaccharides bind selectively to lymphocytes from lipopolysaccharide high-responder mouse strains.

Three different concentrations of horseradish peroxidase-labelled lipopolysaccharide (LPS-HRP) were added in vitro to spleen cells from the LPS high-responder strain C3H/Tif and to cells from the low-responder strain C3H/HeJ. After being washed and fixed the cells were exposed to the substrate and prepared for electron microscopy. After addition of 7 and 0.7 microgram/ml of labelled LPS only lymphocytes from the high-responder strain were labelled. About 5-10% of the cells from C3H/Tif bound LPS, which is in accordance with the known frequency of B cells possessing the genetically determined LPS receptor. At the highest dose of labelled LPS (70 microgram/ml) a large proportion of lymphocytes from the low-responder strain also bound LPS. Erythrocytes from both strains bound LPS at all concentrations. It is concluded that LPS-HRP allows the detection at the cellular level of LPS binding to the genetically controlled membrane receptor for LPS.

Animals↗
PubMed1977

Inheritance of lipopolysaccharide-enhanced nonspecific resistance to infection and of susceptibility to endotoxic shock in lipopolysaccharide low-responder mice.

In a previous study, we demonstrated that lipopolysaccharide (LPS) and other bacterial immunostimulants, in contrast to their activity in a closely related high-responder subline, failed to elicit nonspecific resistance in LPS low-responder mice against Klebsiella pneumoniae infection. To investigate the type of inheritance controlling the LPS-induced nonspecific resistance to infection, the present study was performed in low- and high-responder C3H sublines and in F1 and F2 hybrids. In addition, F1 mice were backcrossed to each parental type. Inheritance of susceptibility to endotoxin was also tested in both sublines and their hybrids and backcross progeny. For these latter assays, mice were previously adrenalectomized because removal of this gland considerably enhances their sensitivity. Our present findings are consistent with the hypothesis that LPS enhances nonspecific resistance to infection and that susceptibility to endotoxin shock in the absence of corticoids may be determined by a single autosomal dominant gene.

Adrenalectomy↗
PubMed1977

Mitogenic response of mouse spleen cells and gelation of limulus lysate by lipopolysaccharide of Yersinia pestis and evidence for neutralization of lipopolysaccharide by polymyxin B.

Lipopolysaccharide (LPS) extracted with phenol and water from Yersinia pestis was compared with LPS of Escherichia coli for stimulation of deoxyribonucleic acid synthesis in mouse spleen cells (lymphocyte mitogenesis), gelation of limulus lysate, pyrogenicity in the rabbit, and susceptibility to inhibition of these activities by polymyxin B sulfate (PBS). LPS of Y. pestis stimulated deoxyribonucleic acid synthesis in mouse spleen cell cultures over the same quantitative range as LPS of E. coli. In the limulus tests and rabbit pyrogenicity studies, the LPS of Y. pestis was active but about 10 times less potent than E. coli LPS on a weight basis. PBS in concentrations from 1 to 10 microgram/ml diminished the rate of deoxyribonucleic acid synthesis in spleen cell cultures stimulated by LPS of both Y. pestis and E. coli. Addition of PBS to LPS of both Y. pestis and E. coli in a ratio of 100 parts of PBS to 1 part of LPS by weight increased by 10-fold the concentration of LPS required to produce gelation of limulus lysate and inhibited significantly pyrogenic responses in rabbits. These results demonstrating similarities of LPS of Y. pestis and E. coli may suggest that the pathogenesis of plague is similar to that of other gram-negative bacterial infections.

Endotoxins↗
PubMed1978

Inverse relationship between the susceptibility of lipopolysaccharide (lipid A)-pretreated mice to the hypothermic and lethal effect of lipopolysaccharide.

Mice pretreated (day 0) by a single injection of lipopolysaccharide (LPS) responded with hypothermic tolerance to (LPS) challenge on day 1 and with hypothermic hyperreactivity to LPS challenge on day 4. Reciprocally, mice pretreated similarly but with a higher challenge dose were hyperreactive with respect to LPS lethality on day 1, but highly tolerant to lethality when challenged on day 4. Hyperreactivity to LPS lethality (day 1) was evident from an accelerated onset of death as well as from a reduced 50% lethal dose in pretreated mice, the level of hyperreactivity being more pronounced with higher LPS pretreatment doses. Lethal hyperreactivity, however, was only seen after challenge with a 50% lethal dose of soluble LPS. In contrast, protection to lethality occurred after challenge with a 50% lethal dose of insoluble LPS (day 1). Tolerance to LPS lethality in mice was observed on day 4 after pretreatment with one (day 0) or four daily injections of LPS. Since reciprocal hyperreactivity (day 1) and cross-tolerance to lethality (day 4) could be achieved by treatment with Salmonella smooth- or rough-form LPS as well as with free lipid A, it was concluded that lipid A represents the active principle of LPS in inducing both hyperreactivity and tolerance to the lethal effect of LPS.

Animals↗
PubMed1978

Distribution of endotoxin (lipopolysaccharide) in the tissues of lipopolysaccharide-responsive and -unresponsive mice.

We examined the distribution of bacterial lipopolysaccharide (LPS) in LPS-responsive (C3H/St) and LPS-unresponsive (C3H/HeJ) mice. The results reported here demonstrate that the rates of removal of an immunological or a toxic dose of LPS from the circulation are the same in both strains of mice. C3H/St spleens accumulated significantly more LPS than C3H/HeJ spleens after the intravenous injection of either an immunogenic or a toxic dose of LPS. There was also a greater amount of LPS associated with cells teased from C3H/St spleens compared to those from C3H/HeJ spleens. After a toxic dose of LPS, there was more LPS in C3H/St lymph nodes, adrenals, lungs, kidneys, and heart than in the corresponding C3H/HeJ tissues. The accumulation of more LPS in tissues from C3H/St mice compared to C3H/HeJ mice suggests that these tissues are involved in the pathophysiological and, ultimately, the toxic effects of LPS. The differential accumulation of LPS in the tissues of these two strains may be the reason for the decreased responses of C3H/HeJ mice to LPS.

Animals↗
PubMed1979

Mechanism of lipopolysaccharide-induced tumor necrosis: requirement for lipopolysaccharide-sensitive lymphoreticular cells.

Lipopolysaccharide (LPS) induces rapid necrosis of intradermal fibrosarcomas in mice. The mechanism(s) by which LPS produces tumor necrosis has been investigated using histocompatible LPS-sensitive (C3H/HeN) and LPS-resistant (C3H/HeJ) mouse strains. C3H/HeN- or C3H/HeJ-derived fibrosarcomas were necrotized by LPS when they were grafted onto C3H/HeN mice but were not affected when growing on C3H/HeJ mice, indicating that LPS does not act directly on the tumor itself. In contrast, lethally X-irradiated C3H/HeJ mice exhibit necrosis of their tumors when reconstituted with C3H/HeN bone marrow cells, whereas C3H/HeN mice no longer exert LPS-induced tumor necrosis after the adoptive transfer of C3H/HeJ bone marrow cells. These findings clearly indicate that LPS produces necrosis of tumors by activating host lymphoreticular cells.

Animals↗
PubMed1979

Influence of lipopolysaccharide on graft versus host reactivity of lipopolysaccharide-unresponsive C3H/HeJ mice.

It was initially reported that lipopolysaccharide (LPS)-unresponsive C3H/HeJ mice are refractory to LPS at the B-lymphocyte level, but more recently it has been shown that other cells are similarly unaffected. The current study was undertaken to study an in vivo LPS-modulated disease process involving macrophage-T cell interactions. Adult CBA/J and C3H/HeJ mice were used as spleen donors, and graft versus host reactions were induced in BALB/c neonates. Prior LPS treatment of CBA/J adults decreased the ability of their spleen cells to cause fatal graft versus host disease in BALB/c neonates, whereas no difference was found between injection of spleen cells from normal or LPS-treated C3H/HeJ mice. Similar results were obtained with these cell types when the mouse spleen mixed leukocyte culture system was used. In a carbon clearance assay for stimulation of the reticuloendothelial system with LPS, it was found that the rate of phagocytosis was significantly increased in BALB/c and CBA/J mice 72 h after inoculation of LPS. No stimulation was seen in rate of carbon uptake in the C3H/HeJ animals after treatment with phenol-extracted LPS or with butanol-extracted LPS. An LPS-induced protective serum factor was produced only in the LPS-responsive CBA/J mice and was specific for the syngeneic cells.

Animals↗
PubMed1978

The lipopolysaccharide (R type) as a common antigen of Neisseria gonorrhoeae. II. Use of hen antiserum to gonococcal lipopolysaccharide in a rapid slide test for the identification of N. gonorrhoeae from primary isolates and secondary cultures.

An antiserum has been prepared in hens to R-type gonococcal lipopolysaccharide (LPS) and used in a simple slide-agglutination test for the identification of Neisseria gonorrhoeae. Anti-LPS serum agglutinated gonococcal cells representative of the four colony types of N. gonorrhoeae. Absorption of the antiserum with LPS removed the agglutinating activity. Secondary cultures (1120) were tested without observation of the colony type and all were agglutinated. No agglutination occurred with strains of Neisseria meningitidis, Neisseria lactamica, non-pathogenic Neisseria. Pseudomonas aeruginosa, Branhamella catarrhalis, or with species of lactobacilli and Acinetobacter. Cross-reactivity of the antiserum occurred with some streptococci. The anti-LPS serum was used to identify N. gonorrhoeae in primary isolates from the cervix, urethra, and pharynx. Of 251 gonococcal isolates tested, 249 were agglutinated by the antiserum, while all of the corresponding second cultures were agglutinated. The antiserum did not agglutinate N. meningitidis found in primary isolates from pharyngeal specimens. Anti-LPS hen serum should be useful for the rapid identification of N. gonorrhoeae in primary isolates or secondary cultures.

Agglutination Tests↗
PubMed1977

Immunologic properties of protein-lipopolysaccharide complexes. I. Antibody response of normal, thymectomized, and nude mice to a lysozyme-lipopolysaccharide complex.

The in vivo antibody response to the lysozyme component of a lysozyme-lipopolysaccharide complex has been investigated in normal, thymectomized and nude mice. The splenic PFC response elicited by the complex in CBA mice is 10- to 20-fold higher than the response elicited by lysozyme admixed with LPS. Both lysozyme-LPS complexes and lysozyme + LPS mixtures prime mice for a subsequent secondary anti-lysozyme response. In contrast, thymectomized mice responded poorly to lysozyme-LPS complexes unless reconstituted with splenic T cells. However, nude mice responded as well as Nu/+ controls to the complex. The PFC response of normal and of nude mice was severely depressed by treatment with anti-lymphocyte serum. These findings suggest that T lymphocytes contribute significantly to the enhanced immune responsiveness associated with LPS administration.

Animals↗
PubMed1979

Synergy between T cell-replacing factor and bacterial lipopolysaccharides (LPS) in the primary antibody response in vitro: a model for lipopolysaccharide adjuvant action.

Unfractionated spleen cells, B cells from normal mice, and nu/nu spleen cells respond to the addition of bacterial lipopolysaccharide (LPS) and T-cell-replacing factor (TRF) by production of plaque-forming cells (PFC) in excess of the number expected from the addition of LPS and TRF separately. This synergistic activity is dependent on the presence of the antigen, SRBC. Supernatants of both allogeneic spleen cell mixtures and spleen cells cultured with Con A are effective and synergize best at concentrations suboptimal for their ability to act as TRF alone. Culture supernatants of unstimulated normal or fractionated cell populations are ineffective. Synergy is not dependent on the presence of macrophages in the cultures. Purified LPS free from active contaminants, as well as commercially available LPS, show synergy with TRF. Synergy was seen when TRF was added at initiation of culture or 24 hr later. It is suggested that synergy is the equivalent of LPS adjuvant activity, that the role of T cells in LPS adjuvanticity is that of a conventional cooperating cell, and the LPS acts as an adjuvant by inducing B cells to become more sensitive to T cell helper factors.

Adjuvants, Immunologic↗
PubMed1979

Mechanisms of lipopolysaccharide-initiated rabbit platelet responses. II. Evidence that lipid A is responsible for binding of lipopolysaccharide to the platelet.

The mechanism of bacterial lipopolysaccharide-(LPS) initiated, complement-(C) mediated rabbit platelet lysis has been examined. The results of these studies support our previous observations that activation of the alternative C pathway is required for platelet lysis and that preparations of LPS that activate only the classical pathway (e.g., lipid A) do not cause lysis. The temporal relationship of the interaction of the LPS with the platelet before the addition of plasma suggests a time-dependent association of the LPS with the platelet. On the basis of a number of experiments, including inhibition with polymyxin B, treatment of LPS with alkali, and blocking experiments with polysaccharide-free LPS preparations, it is concluded that the lipid A region of the LPS molecule is responsible for attaching the LPS to the platelet. Finally, a comparison of the activity of lipid A-associated protein-LPS complexes with protein-free LPS demonstrated that an equivalent extent of platelet lysis was achieved with one-one hundredth the concentration of the former as that required for protein-free LPS. The data suggest that LAP facilitates attachment of the LPS to the platelet.

Animals↗