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B Lindner

Publications and source records attributed to B Lindner.

At least 55 records · Page 3Linked to original sources
PubMed1999

Isolation and structural analysis of phosphorylated oligosaccharides obtained from Escherichia coli J-5 lipopolysaccharide.

The chemical structure of the phosphorylated lipopolysaccharide (LPS) of Escherichia coli J-5 was investigated because it is of biomedical interest in the context of septic shock, a syndrome often encountered in nosocomial infections with gram-negative pathogens. The successive de-O-acylation and de-N-acylation of J-5 LPS yielded phosphorylated oligosaccharides which represent the complete carbohydrate backbone. Five compounds were separated by high-performance anion-exchange chromatography and analysed by one-dimensional and two-dimensional homonuclear and heteronuclear 1H-NMR, 13C-NMR and 31P-NMR spectroscopy. The main product was a nonasaccharide of the structure alpha-D-Glcp-(1-->3)-[alpha-D-GlcpN- (1-->7)-alpha-L,D-Hepp-(1-->7)]-alpha-L,D-Hepp-(1-->3)-alpha -L, D-Hepp-4P-(1-->5)-[alpha-Kdop-(2-->4)]-alpha-Kdop-(2-- >6)-beta-D-GlcpN-4p- (1-->6)-alpha-D-GlcN-1P wherein all sugars are present as D-pyranoses. Hep and Kdo represent L-glycero-D-manno-heptose and 3-deoxy-D-manno-oct-2-ulosonic acid, respectively. In addition, two octasaccharides and two heptasaccharides were isolated that were partial structures of the nonasaccharide. In one octasaccharide the terminal alpha-D-GlcpN was missing and an additional phosphate group linked to O4 of the branched heptose was present, whereas in the other octasaccharide the side-chain Kdo was missing. In both heptasaccharides the side-chain alpha-D-GlcpN-(1-->7)-L-alpha-D-Hepp-disaccharide was absent; they differed in their phosphate substitution. Whereas both heptasaccharides contained two phosphates in the lipid-A backbone (beta-1,6-linked GlcpN-disaccharide at the reducing end) and one phosphate group at O4 of the first heptose, only one of them was additionally substituted with phosphate at O4 of the second heptose.

Carbohydrate Sequence↗
PubMed1999

Analytical approach to the stochastic FitzHugh-Nagumo system and coherence resonance.

We consider the FitzHugh-Nagumo system under the influence of white Gaussian noise in the excitable regime. We present an analytical approximation in the limit of fast activator time scale. Marginal probability densities of a reduced system and dynamical quantities such as the pulse rate are found and the mean interspike interval and its relative standard deviation are investigated. The latter quantities allow a quantitative description of the phenomenon of coherence resonance, as comparisons with simulations show.

Action Potentials↗
PubMed1998

Molecular mechanisms of polymyxin B-membrane interactions: direct correlation between surface charge density and self-promoted transport.

We have studied the interaction of the polycationic peptide antibiotic polymyxin B (PMB) with asymmetric planar bilayer membranes via electrical measurements. The bilayers were of different compositions, including those of the lipid matrices of the outer membranes of various species of Gram-negative bacteria. One leaflet, representing the bacterial inner leaflet, consisted of a phospholipid mixture (PL; phosphatidylethanolamine, -glycerol, and diphosphatidylglycerol in a molar ratio of 81:17:2). The other (outer) leaflet consisted either of lipopolysaccharide (LPS) from deep rough mutants of PMB-sensitive (Escherichia coli F515) or -resistant strains (Proteus mirabilis R45), glycosphingolipid (GSL-1) from Sphingomonas paucimobilis IAM 12576, or phospholipids (phosphatidylglycerol, diphytanoyl-phosphatidylcholine). In all membrane systems, the addition of PMB to the outer leaflet led to the induction of current fluctuations due to transient membrane lesions. The minimal PMB concentration required for the induction of the lesions and their size correlated with the charge of the lipid molecules. In the membrane system resembling the lipid matrix of a PMB-sensitive strain (F515 LPS/PL), the diameters of the lesions were large enough (d = 2.4 nm +/- 8%) to allow PMB molecules to permeate (self-promoted transport), but in all other systems they were too small. A comparison of these phenomena with membrane effects induced by detergents (dodecyltriphenylphosphonium bromide, dodecyltrimethylammonium bromide, sodiumdodecylsulfate) revealed a detergent-like mechanism of the PMB-membrane interaction.

Anti-Bacterial Agents↗
PubMed1998

The structure of the lipopolysaccharide from Klebsiella oxytoca rough mutant R29 (O1-/K29-).

The lipopolysaccharide from Klebsiella oxytoca rough mutant R29 (O1-/K29-) has been isolated and its complete structure has been elucidated by compositional analyses, NMR spectroscopy, and laser-desorption mass spectrometry. The carbohydrate backbone has the structure [formula: see text] of which the GlcN residues (the lipid A backbone) are acylated by 14:(3-OH) (amide-linked) and 12:0, 14:0(3-OH)(ester-linked) fatty acids.

Carbohydrate Sequence↗
PubMed1998

[Limits of beryllium detection with laser microprobe mass spectrometry (LAMMS)].

Search for beryllium (Be) in tissues or urine in suspected beryllium disease is often disappointing due to inferior sensitivity of the methods employed. We evaluated the clinical use of laser microprobe mass spectrometry (LAMMS) for measurement of Be and detected the metal to a minimum concentration of 1 microM. We then investigated the biological relevance of this concentration. We looked at the alveolar macrophages in 7 patients subsequent to an incubation period of 24 h as well as peripheral blood mononuclear cells (PBMNC) and various cell lines with and without addition of beryllium sulfate (BeSO4). We also investigated skin biopsies of two patients 28 days after intracutaneous injections of BeSO4 (beryllium skin testing) and alveolar macrophages of A/J mice at various time intervals after a beryllium sensitisation protocol and a single intratracheal injection of BeSO4 (maximum interval: 15 weeks). Be was not defectable in native patient alveolar macrophages (AM), but in 6 of 7 cases after coincubation with BeSO4. There was no significant Be signal in any analysed PBMNC sample or cell line--even after coincubation with Be--or in the skin probes. Murine AM, however, had incorporated significant amounts of Be, which were detectable until the end of the experiments 15 weeks later. We conclude that concentrations of Be in acute disease (here, inoculation of Be in mice) exceed 1 microM and are thus detectable by LAMMS. On the other hand, concentrations in chronic processes (in this cosar, skin testing) are below the detection limits of LAMMS. Further results suggest compartmentalisation of the immune processes induced by Be because the alveolar macrophages were able to incorporate Be while PBMNC were not and because AM--at least in the animal experiments--seem to store Be intracellularly.

Adult↗
PubMed1997

Elucidation of the structure of the core region and the complete structure of the R-type lipopolysaccharide of Erwinia carotovora FERM P-7576.

An R-type lipopolysaccharide (LPS) from Erwinia carotovora strain FERM P-7576 was studied after strong alkaline degradation and mild acid hydrolysis. The resulting products were analyzed by fast-atom bombardment mass spectrometry, one- and two-dimensional 1H and 13C NMR spectroscopy, dephosphorylation and methylation analysis. The following structure was proposed for the core region of the LPS: [formula in text] where Hep is L-glycero-D-manno-heptose and Kdo is 3-deoxy-D-manno-octulosonic acid. Some LPS species lack the beta-D-Galp residue or the beta-D-Galp-(1-->7)-alpha-Hepp disaccharide. With the known structures of lipid A [Fukuoka, S., Kamishima, H., Nagawa, Y., Nakanishi, H., Ishikawa, K., Niwa, Y., Tamiya, E. & Karube, I. (1992) Arch. Microbiol. 157, 311-318] and the core moiety, the complete LPS structure was established and confirmed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry of the native and O-deacylated LPS.

Carbohydrate Conformation↗
PubMed1997

Mechanisms of action of the bactericidal/permeability-increasing protein BPI on endotoxin and phospholipid monolayers and aggregates.

We have investigated the mechanisms of interaction of the recombinant N-terminal portion of bactericidal/permeability-increasing protein, rBPI21, with lipopolysaccharide (LPS) isolated from enterobacterial deep rough mutant strains. Experimentally, the ability of rBPI21 to form monolayers at the air/water interface and its action on lipid monolayers were analyzed. We have further studied the interaction of rBPI21 with aggregates from phospholipids and Re mutant LPS by infrared and resonance energy transfer spectroscopy and laser Doppler velocimetry. From monolayer experiments, the molecular area of a single rBPI21 molecule was estimated to be about 12 nm2. At lateral pressures of </=25 mN/m, rBPI21 incorporated into monolayers from negatively charged LPS and phosphatidylglycerol (PG) but not into those from neutral phosphatidylcholine. rBPI21 incorporated not only into monolayers but also into liposomes made from or containing negatively charged phospholipids, reducing the absolute value of the zeta-potential of LPS and PG aggregates. Furthermore, due to intercalation, rBPI21 caused the rigidification of the acyl chains of lipids in the gel as well as in the fluid phase and significantly immobilized their phosphate groups. High concentrations of Mg2+ ions were found to have a protective effect against the action of rBPI21. On the basis of these results, the biophysical characteristics of rBPI21 are discussed and a model is proposed as to how the rBPI21-induced influence on lipid monolayers and bilayers could explain rBPI21-mediated effects on the bacterial membrane.

Anti-Infective Agents↗
PubMed1997

Comparison of natural and recombinant isoforms of grass pollen allergens.

More than 95% of grass pollen allergic patients possess IgE antibodies against grass group I, a heterogeneous group of glycoproteins found in all temperate grasses. We studied the structural variability of the group I allergens in single species and among different grasses. By 2-DE blotting using patients' IgE and monoclonal antibodies, we detected IgE-reactive isoforms with molecular masses between 32 and 37 kDa and focusing in a wide pI ranging from 4.7 to 7.6. While the group I allergens of timothy grass (Phl p 1) were composed of 37 and 35 kDa components, only single isoforms were found for ryegrass (Lol p 1) and velvet grass (Hol l 1): 32 and 34 kDa, respectively. By N-terminal microsequencing we determined single amino acid substitutions in different-sized group I allergens. The post-translational modifications (one N-glycosylation site, two hydroxylated proline residues and seven cysteine residues for potential disulfide formations), which contribute to IgE reactivity, were identical in all. From the cDNA sequences we deduced protein sequence homologies > 90%, a result which might explain the high IgE cross-reactivity among the grasses. In order to test whether recombinant group I grass allergens can act as substitutes for the natural forms, we expressed rPhl p 1 in E. coli and in P. pasteuris. 2-DE immunoblotting again demonstrated a microheterogeneity in molecular mass and pI. While the E. coli products were free from post-translational modifications, rPhl p 1 from Pichia is a heterogeneous glycoprotein fraction with a carbohydrate content of about 15%. This rPhl p 1 is hyperglycosylated compared to the nPhl p 1, which only has a 5% carbohydrate content.

Allergens↗
PubMed1997

Structural characterization of the lipid A component of Helicobacter pylori rough- and smooth-form lipopolysaccharides.

The chemical structure of free lipid A isolated from rough- and smooth-form lipopolysaccharides (R-LPS and S-LPS, respectively) of the human gastroduodenal pathogen Helicobacter pylori was elucidated by compositional and degradative analysis, nuclear magnetic resonance spectroscopy, and mass spectrometry. The predominant molecular species in both lipid A components are identical and tetraacylated, but a second molecular species which is hexaacylated is also present in lipid A from S-LPS. Despite differences in substitution by acyl chains, the hydrophilic backbone of the molecules consisted of beta(1,6)-linked D-glucosamine (GlcN) disaccharide 1-phosphate. Because of microheterogeneity, nonstoichiometric amounts of ethanolamine-phosphate were also linked to the glycosidic hydroxyl group. In S-LPS, but not in R-LPS, the hydroxyl group at position 4' was partially substituted by another phosphate group. Considerable variation in the distribution of fatty acids on the lipid A backbone was revealed by laser desorption mass spectrometry. In tetraacyl lipid A, the amino group of the reducing GlcN carried (R)-3-hydroxyoctadecanoic acid (position 2), that of the nonreducing GlcN carried (R)-3-(octadecanoyloxy)octadecanoic acid (position 2'), and ester-bound (R)-3-hydroxyhexadecanoic acid was attached at position 3. Hexaacyl lipid A had a similar substitution by fatty acids, but in addition, ester-bound (R)-3-(dodecanoyloxy)hexadecanoic acid or (R)-3(tetradecanoyloxy)hexadecanoic acid was attached at position 3'. The predominant absence of ester-bound 4'-phosphate and the presence of tetraacyl lipid A with fatty acids of 16 to 18 carbons in length differentiate H. pylori lipid A from that of other bacterial species and help explain the low endotoxic and biological activities of H. pylori LPS.

Ethanolamine↗
PubMed1996

Characterization of lipopolysaccharides of polymyxin-resistant and polymyxin-sensitive Klebsiella pneumoniae O3.

Lipopolysaccharides isolated from the polymyxin-resistant Klebsiella pneumoniae O3 mutant OM-5 and its polymyxin-sensitive parent LEN-1 were analyzed for chemical composition, and their lipid A portions were structurally characterized. The lipopolysaccharide of OM-5 contained approximately five times more 4-amino-4-deoxy-L-arabinopyranose than that of LEN-1. Other saccharide and phosphate components exhibited no significant differences. Structural characterization, including analyses by phosphorus magnetic resonance spectroscopy and by fast atom bombardment mass spectrometry, revealed a novel type of lipid A. In the OM-5 lipopolysaccharide, both phosphates of lipid A were almost totally present as phosphodiesters with 4-amino-4-deoxy-L-arabinopyranose. In the sensitive-type LEN-1 lipid A, the extent of this substitution was much lower, especially in the glycosidically linked phosphate. Phosphate in these K. pneumoniae lipopolysaccharides was almost exclusively found in lipid A. These results show that cationic substituents of phosphates of lipid A play a decisive role in determining polymyxin reactivity. OM-5 was also found to contain a large proportion of heptaacyl lipid A, which represented only a small fraction of lipid A in LEN-1.

Carbohydrate Sequence↗
PubMed1995

The lipopolysaccharide of Legionella pneumophila serogroup 1 (strain Philadelphia 1): chemical structure and biological significance.

The lipopolysaccharide (LPS, endotoxin) of Legionella pneumophila serogroup 1 (Philadelphia 1) exhibits peculiar chemical features which may account for its importance as a bacterial virulence factor. The O-chain of this LPS constitutes a homopolymer of an unusual sugar, 5-acetamidino-7-acetamido-8-O-acetyl-3,5,7, 9-tetradeoxy-D-glycero-L-galacto-nonulosonic acid (legionaminic acid) of which about 10-75 residues are present. Due to the lack of free hydroxyl groups, this homopolymer renders the cell surface highly hydrophobic and, therefore, supports adherence to the membrane of target cells including alveolar macrophages. Investigations of the serological specificity of the serogroup 1 LPS revealed a monoclonal antibody (mAb 3/1) which recognizes an epitope located in the environment of the 8-O-acetyl group of legionaminic acid. According to epidemiological studies, this determinant appears to be associated with L. pneumophila virulence. The outer core oligosaccharide of L. pneumophila LPS exhibits also hydrophobic properties due to the presence of N- and O-acetyl groups as well as 6-deoxy sugars. The inner core expresses both similarities and differences as compared to enterobacterial core oligosaccharides in containing Kdo but lacking heptose and phosphate groups. Lipid A possesses some unique structural features since its backbone consists of a bisphosphorylated beta-GlcpN3N-(1-->6)-GlcpN3N disaccharide with only amide-linked acyl groups having 14-22 carbon atoms. Long chain fatty acids [28:0(27-oxo) and 27:0-dioic] possessing the double length as enterobacterial acyl groups, may be responsible for the low endotoxicity of L. pneumophila lipid A.

Animals↗
PubMed1994

Chemical structure of the lipid A component of lipopolysaccharides of the genus Pectinatus.

The chemical structure of the lipid A components of smooth-type lipopolysaccharides isolated from the type strains of strictly anaerobic beer-spoilage bacteria Pectinatus cerevisiiphilus and Pectinatus frisingensis were analyzed. The hydrophilic backbone of lipid A was shown, by controlled degradation of lipopolysaccharide combined with chemical assays and 31P-NMR spectroscopy, to consist of the common beta 1-6-linked disaccharide of pyranosidic 2-deoxy-glucosamine (GlcN), phosphorylated at the glycosidic position and at position 4'. In de-O-acylated lipopolysaccharide, the latter phosphate was shown to be quantitatively substituted with 4-amino-4-deoxyarabinose, whereas the glycosidically linked phosphate was present as a monoester. Laser-desorption mass spectrometry of free dephosphorylated lipid A revealed that the distal (non-reducing) GlcN was substituted at positions 2' and 3' with (R)-3-(undecanoyloxy)tridecanoic acid, whereas the reducing GlcN carried two unsubstituted (R)-3-hydroxytetradecanoic acids at positions 2 and 3. The lipid A of both Pectinatus species were thus of the asymmetric hexaacyl type. The linkage of lipid A to polysaccharide in the lipopolysaccharide was relatively resistant to acid-catalyzed hydrolysis, enabling the preparation of a dephosphorylated and deacylated saccharide backbone. Methylation analysis of the backbone revealed that position 6' of the distal GlcN of lipid A was the attachment site of the polysaccharide. Despite the quantitative substitution of the lipid A 4'-phosphate by 4-amino-4-deoxyarabinose, which theoretically should render the bacteria resistant to polymyxin, P. cerevisiiphilus was shown to be susceptible to this antibiotic. P. cerevisiiphilus was, however, also susceptibile to vancomycin and bacitracin, indicating that the outer membrane of this bacterium does not act as an effective permeability barrier.

Amino Sugars↗
PubMed1994

Widespread aluminium deposition in extracerebral organ systems of patients with dialysis-associated encephalopathy.

We have described new silver-staining methods for the demonstration of lesions in senile dementia of the Alzheimer type. The same procedure was used to visualize characteristic aluminium (Al)-containing inclusions in choroid epithelium, glia and neurons of the central nervous system in dialysis-associated encephalopathy (DAE). Here we describe the patterns and degree of Al deposition in extracerebral tissues of 12 DAE autopsy cases. Light microscopy of silver-stained paraffin sections demonstrated autonomic ganglion cells filled with numerous intracytoplasmic black-stained fine granular inclusions, which were also seen in endocrine tissues (pituitary, parathyroid and adrenal) and in Leydig cells. Heart, liver cells and the testicular tubules were involved, but decalcified bones, haematopoetic elements, hyperplastic epithelium and one case of malignant epithelium lacked inclusions. Laser microprobe mass analysis revealed prominent Al-related mass signals within the en-bloc silver-stained inclusions which were seen at low intensity in adjacent non-stained structures. Electron microscopy demonstrated accumulations of small electron-dense granules intermingling with lipopigments.

Adult↗
PubMed1993

Chemical structure of the lipid A of Escherichia coli J-5.

The lipopolysaccharide, and particularly its lipid A moiety, of the J-5 mutant of Escherichia coli O111 plays a central role in studies on potential induction of cross-reactive and cross-protective antibodies, however, its chemical and antigenic structure was hitherto unknown. Here, the chemical structure of the J-5 lipid A is reported. It is composed of the bisphosphorylated disaccharide beta-D-GlcpN-4-P-(1-6)-alpha-D-GlcpN-1-P which carries four residues of 3-hydroxytetradecanoic acid, one each at positions 2, 3, 2', and 3'. The hydroxyl groups of the acyl residues at 2' and 3' are esterified with dodecanoic and tetradecanoic acid, respectively. The hydroxyl group at C-6' functions in the lipopolysaccharide as the attachment site of the core oligosaccharide. Furthermore, a new method to isolate the hydrophilic backbone, i.e. the 1,4'-bisphosphorylated glucosamine disaccharide, and its structural analysis by 1H-, 13C-, and 31P-NMR spectroscopy, are described, leading to a new and easier strategy in structural analysis of lipid A from bacterial lipopolysaccharides.

Carbohydrate Sequence↗
PubMed1993

Defective biosynthesis of the lipid A component of temperature-sensitive firA (omsA) mutant of Escherichia coli.

The biosynthesis of lipid A component was shown to be defective in a temperature-sensitive firA mutant of Escherichia coli. Cells were biosynthetically labelled with [14C]acetate and incorporation of radioactivity into the glycerophospholipid compared to lipid A fractions was measured. The lipid A/glycerophospholipid biosynthesis ratio of the firA mutant at 37 degrees C was approximately 50%, and at the nonpermissive temperature of 42 degrees C was less than 20% of that observed in the corresponding wild-type strain. Analysis of radiolabelled lipid A 4'-monophosphate derivatives and glycerophospholipids by thin-layer chromatography revealed that the firA mutant at 42 degrees C elaborated an altered lipid A, and its phosphatidylglycerol content was low. The chemical composition of the extracted lipopolysaccharides differed significantly between the firA and the wild-type strain only in the proportion of hexadecanoic acid, which was minimal in the wild type grown at 37 degrees C and 42 degrees C and in firA lipopolysaccharide grown at 37 degrees C. In the firA mutant lipopolysaccharide produced at 42 degrees C, hexadecanoic acid was present in approximately every third molecule, attached to the hydroxyl group of the amide-linked (R)-3-hydroxytetradecanoic acid at the reducing glucosamine of lipid A. Inspection of dephosphorylated free lipid A preparations by laser-desorption mass spectrometry confirmed that significant amounts of heptaacyl lipid A was elaborated by the firA strain grown at 42 degrees C.

Acyltransferases↗
PubMed1992

Structural characterization of the lipid A component of pathogenic Neisseria meningitidis.

The lipid A component of meningococcal lipopolysaccharide was structurally characterized by using chemical modification methods, methylation analysis, 31P nuclear magnetic resonance, and laser desorption mass spectroscopy. It was shown that Neisseria meningitidis lipid A consists of a 1,4'-bisphosphorylated beta(1'----6)-linked D-glucosamine disaccharide (lipid A backbone), both phosphate groups being largely replaced by O-phosphorylethanolamine. This disaccharide harbors two nonsubstituted hydroxyl groups at positions 4 and 6', the latter representing the attachment site of the oligosaccharide portion in lipopolysaccharide. In addition, it is substituted by up to six fatty acid residues. In the major lipid A component, representing a hexaacyl species, the hydroxyl groups at positions 3 and 3' carry (R)-3-hydroxydodecanoic acid [12:0(3-OH)], whereas the amino groups at positions 2 and 2' are substituted by (R)-3-(dodecanoyloxy)tetradecanoic acid [3-O(12:0)-14:0]. A minor portion was present as a tetraacyl lipid A component lacking either dodecanoic acid (12:0) or 12:0 and 12:0(3-OH). N. meningitidis lipid A, therefore, significantly differs from Escherichia coli lipid A by the nature and locations of fatty acids and the substitution of O-phosphorylethanolamine for the nonglycosyl (4'-P) and glycosyl phosphate.

Fatty Acids↗
PubMed1991

Structural characterization of the lipid A component of Pseudomonas aeruginosa wild-type and rough mutant lipopolysaccharides.

The structure of the lipid A component of lipopolysaccharides isolated from two wild-type strains (Fisher 2 and 7) and one rough mutant (PAC 605) of Pseudomonas aeruginosa was investigated using chemical analysis, methylation analysis, combined gas-liquid chromatography/mass spectrometry, laser-desorption mass spectrometry and NMR spectroscopy. The lipid A backbone was found to consist of a pyranosidic beta 1,6-linked D-glucosamine disaccharide [beta-D-GlcpN-(1----6)-D-GlcpN], phosphorylated in positions 4' and 1. Position 6' of the beta-D-GlcpN-(1----6)-D-GlcpN disaccharide was identified as the attachment site of the core oligosaccharide and the hydroxyl group at C-4 was not substituted. Lipid A of the three P. aeruginosa strains expressed heterogeneity with regard to the degree of acylation: a hexaacyl as well as a pentaacyl component were structurally characterized. The hexaacyl lipid A contains two amide-bound 3-O-acylated (R)-3-hydroxydodecanoic acid groups [12:0(3-OH)] at positions 2 and 2' of the GlcN dissacharide and two ester-bound (R)-3-hydroxydecanoic acid groups [10:0(3-OH)] at positions 3 and 3'. The pentaacyl species, which represents the major lipid A component, lacks one 10:0(3-OH) residue, the hydroxyl group in position 3 of the reducing GlcN residue being free. In both hexa- and pentaacyl lipid A the 3-hydroxyl group of the two amide-linked 12:0(3-OH) residues are acylated by either dodecanoic (12:0) or (S)-2-hydroxydodecanoic acid [12:0(2-OH)], the lipid A species with two 12:0(2-OH) residues, however, being absent. The presence of only five acyl residues in the major lipid A fraction may account for the low endotoxic activity observed with P. aeruginosa lipopolysaccharide.

Carbohydrate Conformation↗