Biomedical subjects

W Kaca

Publications and source records attributed to W Kaca.

At least 37 records · Page 2Linked to original sources

PubMed1999

Structural and serological studies on the O-antigen of Proteus mirabilis O14, a new polysaccharide containing 2-[(R)-1-carboxyethylamino]ethyl phosphate.

An O-specific polysaccharide was obtained by mild acid degradation of Proteus mirabilis O14 lipopolysaccharide (LPS) and found to contain D-galactose, 2-acetamido-2-deoxy-D-glalactose, phosphate, N-(2-hydroxyethyl)-D-alanine (D-AlaEtn), and O-acetyl groups. Studies of the initial and O-deacetylated polysaccharides using one- and two-dimensional 1H- and 13C-NMR spectroscopy, including COSY, TOCSY, NOESY, H-detected 1H,13C heteronuclear multiple-quantum coherence, and heteronuclear multiple-bond correlation experiments, demonstrated the following structure of the repeating unit: [equation: see text] This is the second bacterial polysaccharide reported to contain alpha-D-Galp6PAlaEtn, whereas the first one was the O-antigen of P. mirabilis EU313 taken erroneously as strain PrK 6/57 from the O3 serogroup [Vinogradov, E. V., Kaca, W., Shashkov, A.S., Krajewska-Pietrasik, D., Rozalski, A., Knirel, Y.A. & Kochetkov, N.K. (1990) Eur. J. Biochem., 188, 645-651]. Anti-(P. mirabilis O14) serum cross-reacted with LPS of P. mirabilis EU313 and vice versa in passive hemolysis and ELISA. Absorption of both O-antisera with the heterologous LPS decreased markedly but did not abolish the reaction with the homologous LPS. These and chemical data indicated that both strains have similar but not identical O-antigens. Therefore, we propose that P. mirabilis EU313 should belong to a new subgroup of the O14 serogroup.

Carbohydrate Conformation↗

PubMed1999

Investigation of influence of Proteus mirabilis LPS polysaccharide part on the murine immune cells activation.

The biological activities were investigated of Proteus mirabilis lipopolysaccharides (LPSs) and their fragments, namely, the induction of nitric oxide (NO) and interleukin 1 (IL-1) synthesis by murine macrophages and the proliferation of murine spleen cells. The O-specific polysaccharide (F1), core oligosaccharide (F2) and lipid A were as effective as intact LPS in stimulating murine macrophages to produce NO. IL-1 synthesis was also induced by all studied types of endotoxins (S, Ra, Re) and partial structures, however F1, F2 and lipid A fractions required the presence of serum. In contrast to LPS, the O-specific polysaccharide, core oligosaccharide and lipid A were not able to induce the blast response of murine non-adherent splenocytes.

Animals↗

PubMed1999

Stimulatory effects of endotoxin on the platelet secretory process.

The effects of the lipopolysaccharides (LPS) of Proteus mirabilis (smooth and rough types), differing significantly in their composition on the release of compounds stored in specific platelet granules, were studied. There are two main types of secretory granules in blood platelets. Dense granules contain adenine nucleotides, and in alpha-granules different proteins are stored. The LPS were found to cause a dose-dependent release of proteins and adenine nucleotides. In the extracellular medium LDH activity was not present. The results presented in this study indicate that LPS from P. mirabilis act directly on blood platelets and induce the platelet secretory process. In comparison with thrombin, a strong platelet agonist, the action of the endotoxins tested was weak.

Adenine Nucleotides↗

PubMed1998

Structural and immunochemical studies of two cross-reactive Proteus mirabilis O-antigens, O6 and O23, containing beta1-->3-linked 2-acetamido-2-deoxy-D-glucopyranose residues.

A marked serological cross-reactivity was observed by ELISA and a precipitation test between anti-Proteus mirabilis O23 serum and the lipopolysaccharide as well as the O-specific polysaccharide from the Proteus mirabilis strain belonging to serogroup O6. The structures of the O-specific polysaccharides were elucidated using chemical and NMR spectroscopic analyses, and the only common component, 2-acetamido-2-deoxy-beta-D-glucopyranose (beta-D-GlcNAc), was revealed, which was suggested to be responsible for the cross-reactivity observed. Both anti-O23 and anti-O6 sera were shown to react with 1, 3-Linked beta-D-GlcNAc-containing O-antigen from Salmonella enterica ssp. arizonae O59 also. The lack of reactivity of Smith-degraded P. mirabilis O6 O-specific polysaccharide with homologous antiserum indicated the crucial role of alpha-D-glucuronic acid in specific antibody binding.

Acetylglucosamine↗

PubMed1998

Response of blood platelets to Proteus mirabilis lipopolysaccharide.

The effects of the lipopolysaccharide (LPS) of Proteus mirabilis on the production of thiobarbituric acid reactive substances (TBARS) and the generation of superoxide radicals (O2) by pig blood platelets were studied in vitro. The effect of LPS on TBARS formation in platelets was dependent on the concentration of endotoxin. LPS at concentrations above 0.1 microg/10(8) platelets caused the production of TBARS concomitant with the generation of superoxide radicals. The responses of platelets to LPS suggest that endotoxin, like thrombin (a strong platelets agonist), stimulates an enzymatic cascade of platelet arachidonate via cyclooxygenase and produces thromboxane A2 (TXA2) concomitant with malonyldialdehyde (MDA).

Animals↗

PubMed1998

Serological studies of an acid-labile O-polysaccharide of Proteus vulgaris OX19 lipopolysaccharide using human and rabbit antibodies.

In a Weil-Felix test, sera from patients infected with Rickettsia sp. agglutinate Proteus OX types of bacteria and Proteus lipopolysaccharide (LPS) are responsible for the cross-reaction. Data on the character of LPS of one of the OX group strains, Proteus vulgaris OX19, are contradictory, and it remained unclear whether it has an O-polysaccharide (OPS) and is thus LPS of the smooth type (S) or not (rough-type LPS). Our studies showed that P. vulgaris OX19 (strain PZH-24) produces a smooth-type LPS that contains a long-chain OPS, but it undergoes depolymerization during mild acid hydrolysis conventionally used for LPS delipidation and loses the serological activity. An elucidation of the complete structure of OPS demonstrated the presence of a glycosyl phosphate linkage responsible for the acid-lability of the polysaccharide chain. In ELISA, both IgM type antibodies in a Weil-Felix test with human anti-Rickettsia typhi sera and rabbit anti-P. vulgaris OX19 antibodies reacted with OPS. Rabbit antibodies did not inhibit the cross-reaction with human antibodies and thus bind to different epitopes.

Animals↗

PubMed1998

Serum IgG antibodies in children and adults reacting with Helicobacter pylori lipopolysaccharides.

The presence of IgG antibodies reacting with Helicobacter pylori lipopolysaccharides (LPSs) in sera from children and adults diagnosed as H. pylori-infected, as well as healthy persons, was tested. There was no correlation between the production of antibodies reacting with H. pylori surface proteins and LPSs. Also no correlation between reactivity of tested sera with H. pylori antigens and deep rough mutant (Re types) enterobacterial LPSs was revealed. The prevalence of anti-LPS IgG in randomly selected children was relatively high.

Adult↗

PubMed1998

Immunochemical characterization of Bacteroides vulgatus cell-surface antigens.

Capsular polysaccharide (CPS) and lipopolysaccharide (LPS) antigens extracted from three Bacteroides vulgatus strains (serotype specific strain, and two others isolated from normal gut flora and gut of a diabetic patient) were studied. Chemical analysis of CPS and purified LPS antigens was performed. The compositions of sugars, amino acids and fatty acids were shown to be different for each antigen. Rabbit antisera against whole bacterial cells were prepared. All antigens proved to be active in immunoelectrophoresis, SDS-PAGE and immunoblot tests. Several cross reactions in these assays were observed.

Animals↗

PubMed1998

Genomic fingerprinting of Proteus species using repetitive sequence based PCR (rep-PCR).

Three Proteus species P. vulgaris, P. mirabilis and P. penneri have been characterized by repetitive sequence-based PCR. Four families of repetitive sequence based primers REP, ERIC, BOXA1R and BOXA2R, give specific patterns for each Proteus species. Species differentiation was best afforded using BOXA2R for detection of P. mirabilis, either REP-Dt or BOXA1R primers for detection of P. penneri and ERIC primer pair for P. vulgaris.

Bacterial Typing Techniques↗

PubMed1997

Structure of the O-specific polysaccharide of Proteus vulgaris O25 containing 3-O-[(R)-1-carboxyethyl]-D-glucose.

The O-specific polysaccharide of Proteus vulgaris O25 was studied by acid hydrolysis and by 1H-NMR and 13C-NMR spectroscopies, including one-dimensional NOE and two-dimensional COSY and heteronuclear 13C,1H correlation (HETCOR) spectroscopy. The polysaccharide was found to contain 3-O-[(R)-1-carboxyethyl]-D-glucose (D-RGlc), and the following structure of the pentasaccharide repeating unit was established: [structure in text]

Carbohydrate Conformation↗

PubMed1997

Structures of the O-antigens of Proteus bacilli belonging to OX group (serogroups O1-O3) used in Weil-Felix test.

Structures of the O-specific polysaccharide chains of lipopolysaccharides from Proteus group OX strains (serogroups O1-O3) used as antigens in Weil-Felix test for diagnosis of rickettsiosis, were established. From them, the acid-labile polysaccharide of Proteus vulgaris OX19 (O1) is built up of the following branched pentasaccharide repeating units connected via a phosphate group: [structure in text] where QuiNAc stands for 2-acetamido-2,6-dideoxyglucose (N-acetylquinovosamine). The basis of serospecificity of the Proteus group OX antigens and their cross-reactivity with human anti-rickettsial antibodies is discussed.

Antibodies, Bacterial↗

PubMed1997

Structural and serological studies of the O-antigen of the bacterium Proteus vulgaris OX2 (serogroup O2) used in the Weil-Felix test.

Based on monosaccharide analysis and 1H- and 13C-NMR spectroscopy, the following structure of the O-specific polysaccharide chain of Proteus vulgaris OX2 lipopolysaccharide (LPS), which defines the O2 specificity of Proteus, was established: [formula: see text] where L-QuiNAc is N-acetyl-L-quinovosamine (2-acetamido-2,6-dideoxy-L-glucose). Various strains of P. vulgaris OX2 used in the Weil-Felix test for serodiagnosis of rickettsiosis (spotted fevers, except for Rocky Mountain spotted fever) were shown to produce LPS with the same O-specific polysaccharide, which differs structurally and serologically from LPS of P. vulgaris OX19 used as antigen for serodiagnosis of typhus and Rocky Mountain spotted fever. O-Acetyl groups present in the polysaccharide are not important for manifesting the immunospecificity. ELISA confirmed that the epitope responsible for the cross-reactivity between sera from patients with Japanese spotted fever and P. vulgaris OX2 cells is located on the P. vulgaris LPS. At the same time, no cross-reaction was observed between rabbit anti-P. vulgaris OX2 antibodies and the spotted fever group (SFG) rickettsial cells. Therefore, human anti-SFG rickettsial antibodies and rabbit anti-P. vulgaris OX2 antibodies may bind to distinct epitopes on P. vulgaris OX2 LPS, and no epitope recognized by rabbit anti-P. vulgaris OX2 antibodies is present on the LPS or any other surface antigen of SFG rickettsiae.

Carbohydrate Conformation↗

PubMed1997

Structural and serological studies of the O-antigen of the bacterium Proteus mirabilis OXK (serogroup O3) used in the Weil-Felix test.

Sugar analysis and 1H- and 13C-NMR spectroscopic studies showed that various strains of Proteus mirabilis OXK used as antigens in the Weil-Felix test for serodiagnosis of rickettsiosis (scrub typhus) produce lipopolysaccharides (LPSs) with the same O-specific polysaccharide chain having the following structure: [formula: see text] where GlcA and GalA are glucuronic and galacturonic acids, respectively. This polysaccharide which defines the O3 specificity of Proteus and has been found earlier in an unclassified P. mirabilis strain S1959, contains an amide of D-galacturonic acid with L-lysine which plays an important role in manifesting the immunospecificity. A cross-reaction was observed in ELISA between sera from patients with scrub typhus, caused by the bacterium Orientia (Rickettsia) tsutsugamushi, and purified LPS of P. mirabilis OXK, thus suggesting that the common epitope involved in the Weil-Felix test is located on P. mirabilis OXK LPS. Rabbit anti-P. mirabilis OXK antibodies did not cross-react with LPS-lacking O. tsutsugamushi strain Gilliam in dot-blotting and Western blotting, and the nature of the rickettsial antigen responsible for the Weil-Felix reaction remains unknown.

Carbohydrate Conformation↗

PubMed1997

Structure of the acid-labile galactosyl phosphate-containing O-antigen of the bacterium Proteus vulgaris OX19 (serogroup O1) used in the Weil-Felix test.

The structure of the O-specific polysaccharide chain of Proteus vulgaris OX19 lipopolysaccharide which determines the O1 specificity of Proteus and is used in the Weil-Felix test for diagnostics of rickettsiosis was established. On the basis of 1H- and 13 C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected 1H, 13C heteronuclear multiple-quantum coherence (HMQC), and rotating-frame nuclear Overhauser effect spectroscopy (ROESY), it was found that the polysaccharide consists of branched pentasaccharide repeating units containing D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, and 2-acetamido-2,6-dideoxy-D-glucose (QuiNAc, two residues), which are connected to each other via a phosphate group (P): [formula: see text]. The polysaccharide is acid-labile, the glycosyl phosphate linkage being cleaved at pH 4.5 (70 degrees C) to give a phosphorylated pentasaccharide with a galactose residue at the reducing end. Structural analysis of the oligosaccharide and a product of its dephosphorylation with 48% hydrofluoric acid using 1H- and 13C-NMR spectroscopy and electrospray ionization mass spectrometry confirmed the structure of the polysaccharide.

Carbohydrate Conformation↗

PubMed1997

Structure of the O-specific polysaccharide of the bacterium Proteus mirabilis O13 containing a novel component: an amide of D-galacturonic acid with N(epsilon)-(1-carboxyethyl)lysine.

An acidic O-specific polysaccharide was obtained by mild degradation of the lipopolysaccharide of the bacterium Proteus mirabilis O13 and found to contain D-galactose, 2-acetamido-2-deoxy-D-glucose, and N(epsilon)-(1-carboxyethyl)-N(alpha)-(D-galacturonoyl)lysine. On the basis of full acid hydrolysis and 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected heteronuclear 1H, 13C multi-quantum coherence (HMQC), and rotating-frame nuclear Overhauser effect spectroscopy (ROESY), the following structure of the branched trisaccharide repeating unit of the polysaccharide was established [structure: see text]

Amides↗

PubMed1997

Structure of a neutral O-specific polysaccharide of the bacterium Proteus mirabilis O24.

Lipopolysaccharide of the bacterium Proteus mirabilis O24 was found to have a neutral O-specific polysaccharide chain containing D-galactose, 2-acetamido-2-deoxy-D-glucose, and 2-acetamido-2-deoxy-D-galactose in ratios 1:2:1. On the basis of 1H- and 13C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), H-detected 1H, 13C heteronuclear multiple-quantum coherence (HMQC), and nuclear Overhauser effect spectroscopy (NOESY), the following structure of the branched tetrasaccharide repeating unit of the O-specific polysaccharide was established: -->3)-beta-D-GlcpNAc-(1-->4)-beta-D-GalpNAc-(1-->4)-beta-D-GlcpNAc-(1--> [formula: see text] beta-D-Galp.

Carbohydrate Conformation↗

PubMed1996

Structural and serological studies of the O-specific polysaccharide of the bacterium Proteus mirabilis O10 containing L-altruronic acid, a new component of O-antigens.

An acidic O-specific polysaccharide from the lipopolysaccharide of Proteus mirabilis O10 contains 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, D-galacturonic acid, and L-altruronic acid, the last-named sugar having not been found hitherto in O-antigens. Structure of a branched tetrasaccharide repeating unit of the polysaccharide was established by 1H and 13C NMR spectroscopy, including two-dimensional COSY and rotating-frame NOE spectroscopy. The lateral L-altruronic acid residue plays the immunodominant role in manifestation of the O10 specificity of Proteus, whereas a disaccharide fragment of the main chain in common with the O-specific polysaccharide of P. mirabilis O43 provides the one-way serological cross-reactivity between anti-O10 serum and O43-antigen.

Antibodies, Bacterial↗

PubMed1996

Structures of new acidic O-specific polysaccharides of the bacterium Proteus mirabilis serogroups O26 and O30.

The polysaccharide chains of the lipopolysaccharides of the Proteus mirabilis serogroups O26 and O30 were studied using sugar and methylation analysis and 1H and 13C NMR spectroscopy, including two-dimensional correlation spectroscopy and rotating-frame NOE spectroscopy. The polysaccharides were found to be acidic due to the presence of D-galacturonic acid and its amide with L-lysine in serogroup O26 or D-glucuronic acid in serogroup O30, and the structures of their tetrasaccharide repeating units were established. The O26-specific polysaccharide is structurally and serologically related to the O-specific polysaccharide of P. mirabilis O28, which includes amides of D-GalA with L-lysine and L-serine [Radziejewska-Lebrecht, J. et al. (1995) Eur. J. Biochem. 230, 705-712].

Carbohydrate Conformation↗