Sabina Górska-Frączek

Lactobacillus rhamnosus exopolysaccharide ameliorates arthritis induced by the systemic injection of collagen and lipopolysaccharide in DBA/1 mice

Oral administration of some probiotic bacteria (e.g. Lactobacillus rhamnosus) attenuates various types of experimental arthritis, including collagen-induced arthritis (CIA) and inhibits arthritogenic autoantibodies. Much less is known about the possible anti-arthritogenic properties of exopolysaccharide (EPS), the major component of lactic bacteria biofilm. In this study, we asked the question whether systemic administration of EPS derived from L. rhamnosus KL37 depresses the production of anti-collagen IgG and affects the development of CIA in DBA/1 mice. Arthritis was induced employing two models of active CIA, in which mice were immunized with type II collagen (CII) either in the presence of lipopolysaccharide (LPS; mild arthritis with moderate CII-specific IgG production) or with Complete Freund’s Adjuvant and LPS (severe arthritis with massive CII-specific IgG production). Passive CIA was induced by intravenous injection of CII-specific monoclonal antibodies and LPS. Disease progression, the incidence and severity of arthritis, were determined. Serum concentration of CII-specific IgG was measured by enzyme-linked immunosorbent assay. Systemic administration of EPS markedly reduced CII-specific antibody production. Moreover, EPS significantly ameliorated arthritis in the active models of CIA, especially, when LPS alone was used as an adjuvant. In contrast, when arthritogenic antibodies were injected to mice in high amounts, the effect of EPS on the development of passive CIA was negligible and transient. These results show that EPS can suppress active CIA by the inhibition of arthritogenic antibodies production. Therefore, we suggest that EPS or EPS-producing probiotics may be promising agents for the supporting therapy of patients with rheumatoid arthritis.

The structure and immunoreactivity of exopolysaccharide isolated from Lactobacillus johnsonii strain 151

The exopolysaccharide (EPS) structure from Lactobacillus johnsonii strain 151 isolated from the intestinal tract of mice was investigated. Sugar and methylation analyses together with (1)H and (13)C NMR spectroscopy, including two-dimensional (1)H,(1)H COSY, TOCSY, NOESY, and (1)H,(13)C HSQC, HMBC experiments, revealed that the repeating unit of the EPS is the linear pentasaccharide: →6)-α-d-Galp-(1→6)-α-d-Glcp-(1→3)-β-d-Galf-(1→3)-α-d-Glcp-(1→2)-β-d-Galf-(1→ The immunoreactivity of two structurally different exopolysaccharides isolated from L. johnsonii, 151 and 142 (Carbohydr. Res. 2010, 345, 108-114), was compared. Both EPSs differed in their reactivity with antisera. EPS from L. johnsonii 151 reacted with anti-Lactobacillus polyclonal sera against cells of five different strains, while EPS from L. johnsonii 142 was found to react only with its own antiserum. The broader specificity and higher reactivity of EPS from 151 strain than EPS from 142 strain were also observed with human sera. The physiological antibodies recognizing polysaccharide antigens were present in both adults and umbilical cord blood sera. A highly specific EPS 142 bearing strain was isolated from experimentally induced inflammatory bowel disease (IBD) mice, while a strain with EPS 151 isolated from the intestinal tract of healthy mice is characterized by a broad immune reactivity common structure.

Structural studies of the exopolysaccharide consisting of a nonasaccharide repeating unit isolated from Lactobacillus rhamnosus KL37B

A novel structure of exopolysaccharide from the lactic acid bacteria (LAB) Lactobacillus rhamnosus KL37B, from the human intestinal flora, is described. During the structural investigation of the exopolysaccharide it was found that the repeating unit is a nonasaccharide, which is the largest repeating unit found in LAB exopolysaccharides to date. The polysaccharide material was prepared by TCA extraction of a bacterial cell mass, purified by anion-exchange and gel permeation chromatography and characterized using chemical and enzymatic methods. On the basis of monosaccharide and methylation analysis and also 1D and 2D (1)H and (13)C NMR spectroscopy the exopolysaccharide was shown to be composed of the following nonasaccharide repeating unit: The physicochemical cell surface study and adhesive properties indicated distinct surface properties of Lactobacillus rhamnosus strain KL37B with high adhesive abilities to Caco-2 cells, hydrophobicity and slime production, in comparison to other Lactobacillus strains used as controls.

[Enterobacteriaceae infection - diagnosis, antibiotic resistance and prevention].

Intestinal infections caused by rod-shaped bacteria of the Enterobacteriaceae genus are one of the major health hazards in countries where sanitation standards are low. Strains of Shigella, Salmonella, Escherichia and Yersinia are responsible for diarrhea, severe bacillary dysentery, typhoid, other intestinal diseases, as well as genitourinary tract and blood infections. According to the WHO there are 4.5 billion cases every year, of which 1.9 million end in death. This makes intestinal infections third in terms of human disease mortality. In this work we discuss methods of pathogen identification, the mechanism of host-pathogen interaction, and the nature of the hosts immunological response. Due to rising drug resistance we discuss the importance of better pathogen detection, vaccine design and the use of vaccines as a preventive measure against intestinal infections. Special attention is paid to OMP38, a protein isolated from S. flexneri 3a outer membrane. Since it is known that this protein has good immunogenic properties, it can be used as an antigen or carrier for conjugate vaccines.

Structure of the O-polysaccharide of Edwardsiella tarda PCM 1150 containing an amide of D-glucuronic acid with L-alanine.

Mild acid degradation of the lipopolysaccharide of Edwardsiella tarda PCM 1150 afforded an O-polysaccharide, which was isolated by GPC on Sephadex G-50 and studied by sugar and methylation analyses along with 1D and 2D 1H and 13C NMR spectroscopies, including experiments performed in a 9:1 H2O/D2O mixture to detect NH protons and their correlations with CH protons. The O-polysaccharide was found to contain an amide of d-glucuronic acid with l-alanine (d-GlcA6Ala) and the following structure of the branched hexasaccharide repeating unit was established: -->4)-β-D-GlepA6Ala-(1-->4)-α-L-Fucp-(1-->4)-α-D-Glcp-(1-->4)-α-D-Quip-(1-->3)-β-D-GlcpNAc-(1-->3<--1α-D-GalpNAc.

Structure of the O-polysaccharide of Edwardsiella tarda PCM 1156

Mild acid degradation of the lipopolysaccharide of Edwardsiella tarda PCM 1156 afforded an O-polysaccharide, which was isolated by gel-permeation chromatography on Sephadex G-50 and studied by sugar and methylation analyses along with (1)H NMR and (13)C NMR spectroscopy, including 2D (1)H,(1)H COSY, TOCSY, ROESY, (1)H,(13)C HSQC, and HMBC experiments. The following structure of the linear tetrasaccharide repeating unit of the O-polysaccharide was established: [structure: see text].

Surface proteins of bacteria of the genus Bifidobacterium

Beneficial effects due to the presence of probiotic bacteria of the genus Bifidobacterium in the human intestinal tract are still an interesting object of study. So far activities have been confirmed of bifidobacteria in stimulation of the host immune system, stimulation of tumor cell apoptosis, improvement of bowel motility, alleviation of symptoms of lactose intolerance, cholesterol lowering capacity, prevention and treatment of diarrhea and irritable bowel syndrome, alleviation of allergy or atopic dermatitis, maintenance of homeostasis of the intestine, and stimulation of the development of normal intestinal microflora in infants. A multitude of therapeutic properties encourages researchers to investigate the possibility of using the potential of Bifidobacterium in the prevention and treatment of other conditions such as rheumatoid arthritis and depression. Although it is known that the beneficial effects are due to intestinal mucosal colonization by these bacteria, the cell components responsible for the colonization are still not determined. In addition to the beneficial effects of probiotic administration, there were also negative effects including sepsis. Therefore research has been directed to identify specific components of Bifidobacterium responsible for probiotic effects. Currently researchers are focused on identifying, isolating and evaluating the properties of surface proteins that are probably involved in the adhesion of bacterial cells to the intestinal epithelium, improving colonization. This paper is an overview of current knowledge on Bifidobacterium surface proteins. The ways of transport and anchoring proteins in Gram-positive bacterial cells, the assembly of cell wall, and a description of the genus Bifidobacterium are presented.

Structural and serological studies on the O-antigen show that Citrobacter youngae PCM1505 must be classified to a new Citrobacter O-serogroup.

The O-polysaccharide obtained by mild acid hydrolysis of the lipopolysaccharide of Citrobacter youngae PCM1505 was studied by sugar and methylation analyses along with 1D and 2D (1)H and (13)C NMR spectroscopies. The following structure of the tetrasaccharide repeating unit of the polysaccharide was established: [Formula: see text]. Structural and serological data obtained earlier and in this work show that the strain studied is a candidate to a new Citrobacter O-serogroup.