Structure of an acidic O-specific polysaccharide of the bacterium Providencia alcalifaciens O7.

An acidic O-specific polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of the bacterium Providencia alcalifaciens O7 and purified by gel chromatography followed by anion-exchange chromatography. On the basis of full acid hydrolysis, methylation, carboxyl reduction, selective cleavage with anhydrous hydrogen fluoride, and 1H- and 13C-NMR spectroscopy, including two-dimensional 1H,1H homonuclear and H-detected 1H,13C heteronuclear correlation spectroscopy and nuclear Overhauser effect spectroscopy (NOESY), the following structure of the linear tetrasaccharide repeating unit of the polysaccharide was established: [figure], where Rhap2Ac is 2-O-acetylrhamnopyranose.

[An antigenic analysis and the protective properties of the R-form lipopolysaccharides of gram-negative bacteria]. / Antigennyi analiz i protektivnye svoistva lipopolisakharidov R-form nekotorykh gramotritsatel'nykh bakterii.

The antigenic and immunogenic properties of the R-form lipopolysaccharides (R-LPS) of Pseudomonas aeruginosa, Salmonella minnesota, Escherichia coli and Shigella were studied. The results of the study revealed the existence of antigenic relationship between P.aeruginosa R-LPS and R-LPS Escherichia and Shigella. In serological tests no antigenic relationship between P. aeruginosa R-LPS and Salmonella R-LPS was revealed, but as shown in earlier experiments of the protection of mice, Re-glycolipid stimulated protective immunity against Pseudomonas infection in the animals. On the basis of R-LPS obtained from selected P. aeruginosa and Salmonella strains a vaccine was prepared which proved to be effective against infection caused by P. aeruginosa S-strain in experiments on mice. The vaccine induced protection in 40-100% of immunized mice, depending on the scheme of immunization. The vaccine may probably be effective against infections caused by other gram-negative bacteria.

[An immunological study of the cell wall proteins of Pseudomonas aeruginosa]. / Immunologicheskoe izuchenie belkov kletochnoi stenki Pseudomonas aeruginosa.

A preparation containing P. aeruginosa cell-wall proteins with a mol. wt. of 9-55 kD has been obtained from P. aeruginosa by the method of extraction with the use of tris-EDTA buffer. In experiments on mice this protein preparation has shown pronounced protective properties, but, according to the data of Shwartzman's local reaction, proved to be toxic, perhaps due to the admixture of LPS. The purification of the protein preparation from the admixture of LPS will make it possible to obtain an effective vaccine against P. aeruginosa infection.

[The immunological response in volunteer donors immunized with a Pseudomonas vaccine]. / Immunologicheskii otvet u donorov-dobrovol'tsev, immunizirovannykh vaktsinoi psevdomonas.

The trial of experimental vaccine consisting of protective protein antigens of P. aeruginosa cell wall was carried out on 114 volunteers. The vaccine proved to be faintly reactogenic and induced the formation of specific humoral immunity in 98% of the volunteers who retained a high level of anti-P. aeruginosa antibodies in their blood for up to 5 months (the term of observation after the course of immunization was over.

[An experimental study of a lactoglobulin preparation against opportunistic bacteria and salmonellae]. / Eksperimental'noe izuchenie preparata laktoglobulina protiv uslovno-patogennykh bakterii i sal'monell.

A preclinical study of seven batches of lactoglobulin, a new biological preparation against opportunistic bacteria and salmonellae, has been carried out. High antibacterial activity of the preparation with respect to the virulent forms of Salmonella typhimurium, Salmonella enteritidis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus vulgaris, Proteus mirabilis has been established. The preparation has been shown to be safe and nontoxic. The 4-year term of its storage at a temperature of 6 degrees +/- 4 degrees C has been substantiated.

[The serological characteristics of the O antigens of Pseudomonas aeruginosa isolated from patients with a Pseudomonas infection during immunotherapy]. / Serologicheskaia kharakteristika O-antigenov Pseudomonas aeruginosa, vydelennykh ot bol'nykh sinegnoinoi infektsiei v protsesse immunoterapii.

Serologic characteristics of P. aeruginosa O-antigens isolated from patients with P. aeruginosa infection were studied over the course of treatment with anti-P. aeruginosa sheep immunoglobulin. The preparation was used in 54 patients with nongeneralized forms of P. aeruginosa infection (infected wounds, pleural empyema) externally or intraperitoneally. From the clinical material collected from the patients a total of 54 P. aeruginosa strains were isolated. Serologic typing of the isolated strains with factor or group diagnostic agglutinating sera has revealed the O-group composition of the isolated strains; 66% of them were classified with O-groups 2,3, and 6. Serologic variants of the strains isolated from patients proved to be stable over the course of the disease immunotherapy. Analysis of the results of bacteriologic control of immunotherapy. efficacy and the clinical data has demonstrated the efficacy of immunotherapy in 61.1% of cases and its partial effect in 20.4% of cases of P. aeruginosa infection.

[Immune response to a synthetic polysaccharide and protein conjugate]. / Immunnyi otvet k kon"iugatu sinteticheskogo polisakharida s belkom.

Synthetic polysaccharide (S-PS) containing aglycone-spacer with a free amino group was really alpha 1,6-mannan with Cn approximately 10. S-PS was transformed into isothiocyanate derivative by treating it with thiophosgene and engaged into reaction with amino group of bovine serum albumin (BSA) lysine residues. Rabbits were immunized with S-PS-BSA conjugate and antibodies to S-PS titres were estimated by means of ELISA. S-PS-BSA conjugate was proved to provoke specific anti-polysaccharide antibodies formation in rabbits.

[Experimental vaccinal prophylaxis of Pseudomonas aeruginosa burn sepsis]. / Vaktsinoprofilaktika sinegnoinogo ozhogovogo sepsisa v éksperimente.

After the injection of P. aeruginosa live culture under the burned skin of mice sepsis develops within the first 24 hours, finally leading to the death of the animals. The microorganisms can be isolated from the blood, liver, kidneys and mesenterial lymph nodes till day 3 and from the spleen till day 5. After the intraperitoneal injection of P. aeruginosa live culture into mice, sepsis also develops within 24 hours, and the culture can be isolated from the blood and parenchymatous organs till day 3. The LD50 of the culture is equal to 5.1 X 10(6) microbial cells when introduced intraperitoneally and to 30 microbial cells in experimental burn sepsis. Experimental burn sepsis clearly demonstrates the effectiveness of Pseudomonas acellular protein vaccine: its index of effectiveness exceeds 3,000.

[Structure of the O-specific polysaccharides and the protective activity of the lipopolysaccharides in Pseudomonas aeruginosa of 7 immunotypes (after Fisher)]. / Struktura O-spetsificheskikh polisakharidov i protektivnaia aktivnost' lipopolisakharidov Pseudomonas aeruginosa semi immunotipov (po Fisheru).

The structure of O-specific polysaccharides and the protective activity of lipopolysaccharides (LPS) obtained from seven P. aeruginosa immunotypes (according to Fisher's classification) have been studied. The structure of O-specific polysaccharides, immunotypes 2, 3, 4, 5 and 6, is identical to that of polysaccharides of serotypes 011; 0(2a), 2c; 01; 010a, 10b; 07a, 7d respectively. No structural analogs of O-polysaccharide characteristic of immunotypes 1 and 7 have been detected among serotypes classified according to the scheme of Lányi-Bergan-Akatova-Smirnova. The specific character of O-polysaccharides is confirmed by the results of the passive hemagglutination inhibition test, but the data of the passive hemagglutination test indicate that LPS of different immunotypes are antigenically related. As revealed in experiments on the active immunization of mice, LPS of seven immunotypes possess more or less pronounced cross protective properties. The causes of the cross protective activity observed in experiments with these LPS are discussed.

[Characteristics of rhamnan isolated from preparations of Pseudomonas aeruginosa lipopolysaccharides]. / Kharakteristika ramnana, vydelennogo iz preparatov lipopolisakharidov Pseudomonas aeruginosa.

A polysaccharide isolated from the degraded lipopolysaccharides of P. aeruginosa serogroup O7 (Lányi--Bergan classification) was characterized by liquid chromatography, acid hydrolysis, and 1H and 13C NMR spectroscopy. It has molecular mass 15,000 and represents mainly a rhamnan of the structure----2)-alpha-D-Rha-(1----3)-alpha-D-Rha-(1----3)-alpha-D-Rha-(1 ----, identical to the structure of O-specific polysaccharides of Pseudomonas aeruginosa pvs morsprunorum and cerasi. Some minor constituents, such as glucose, mannose, an unknown sugar, and phosphate, are found in the polysaccharide preparation as well. Distribution of the rhamnan in some other P. aeruginosa serogroups is discussed and its identity to the common polysaccharide antigen of P. aeruginosa is suggested.

[Experimental study of the protective activity of vaccines made from 7 Pseudomonas aeruginosa immunotypes]. / Eksperimental'noe izuchenie protektivnoi aktivnosti vaktsin iz semi immunotipov Pseudomonas aeruginosa.

Monovaccines were prepared from seven P. aeruginosa immunotypes (according to Fisher's classification) and three P. aeruginosa production strains belonging to immunotypes 2, 3, and 7. The immunogenic potency of these monovaccines was studied in direct and cross experiments on the active protection of mice. The study revealed that the monovaccines prepared from P. aeruginosa of seven immunotypes possessed both specific and cross protective activity. Protective cross activity was revealed also in the vaccines prepared from the production strains. When tested in mice challenged with the corresponding homologous strains, the monovaccines prepared from immunotypes 2, 3, 4 and 7 proved to possess higher immunogenic potency than monovaccines prepared from immunotypes 1, 5 and 6.

[Interrelation of the enterotoxigenic properties and the antigenic structure of Escherichia]. / O vzaimosviazi énterotoksigennykh svoistv i antigennoi struktury ésherikhii.

The enzymatic signs and serological characteristics of Escherichia enterotoxigenic strains isolated from patients with acute intestinal diseases and from healthy persons were studied. The cultures were subdivided into 24 enzymatic variants and classified with 48 serogroups and 61 serovars. The enterotoxigenic properties of the strains were compared with their serological characteristics and enzymatic signs. The strains, isolated from different persons and classified with the same serovar, belonged to the same variant with respect to the type of enterotoxin they produced (only thermostable enterotoxin, only thermolabile enterotoxin, or both), were similar in the degree of their toxigenicity and belonged, as a rule, to the same enzymatic variant. The data on the presence of manifest interrelation between the enteropathogenicity of Escherichia and their structure, as well as on the stability of the enterotoxigenic properties of these organisms, indicate that in acute intestinal diseases the determination of Escherichia enterotoxigenic strains can be carried out by common bacteriological techniques with the use of specific agglutinating sera.

[Antigenic bacterial polysaccharides. 14. Structure of the O-specific polysaccharide chain of a lipopolysaccharide from Pseudomonas aeruginosa (Lányi)]. / Antigennye polisakharidy bakterii. 14. Struktura O-spetsificheskoi polisakharidnoi tsepi lipopolisakharida Pseudomonas auruginosa (Lányi).

The lipopolysaccharide from Pseudomonas aeruginosa O12 (Lányi classification) gave on mild acid hydrolysis an O-specific polysaccharide built of D-ribose and N-acetyl-D-galactosamine. The disaccharide structure----4)-alpha-GalNAcp-(1----2)-beta-Ribf-(1----for the repeating unit of the polysaccharide was established by nondestructive way involving full interpretation of its 1H- and 13C-NMR-spectra, using homonuclear and selective heteronuclear 13C[1H] double resonances.

[Effect of plasmids on the virulence of Pseudomonas aeruginosa strains in experiments on mice]. / Vliianie plazmid na virulentnost' shtammov Pseudomonas aeruginosa v éksperimentakh na myshakh.

A comparative study of virulence of P. aeruginosa strains PAO containing and not containing plasmids has been made. A number of plasmids which are present in strains PAO decrease their virulence for mice 3-7 times. The virulence-affecting plasmids considerably differ in their biological properties. Bacterial mutations rpm, selected as mutations stabilizing RP4 plasmid in PAO cells, have also been found to affect virulence of bacteria, decreasing its level several times. The introduction of plasmids into PAO cells carrying mutations rpm is not accompanied by decrease of virulence.

The structure and immunochemical specificity of 0-antigens of 03 serogroup Pseudomonas aeruginosa.

Using the method of phenol-aqueous extraction, lipopolysaccharides (LPS) were isolated from 5 strains (subgroups) belonging to 03 serogroup of P. aeruginosa (4). Specific polysaccharides were isolated from the LPS by means of acid hydrolysis. It has been established that the polysaccharides determining O-antigenic specificity have a uniform structure. They consist of repeated trisaccharide links comprising: 2,3(1-acetyl-2-methyl-2-imidazolino-5,4)-2,3-dideoxy-D-mannuronic acid (Im) 2,3-diacetamido-2,3-dideoxy uronic acid with -D-manno-(M) or -L-gulo-(G) configuration and 2-acetamido-2-deoxy-D-fucose (F) with alpha or beta configuration of the glycosidic bond. The structure of 0/3a/3d, 3f polysaccharide has not been definitely cleared up. Serological analysis using passive haemagglutination reaction (PHAR) testifies to the presence of antigenic cross activity of all the five LPS. Antigenic specificity of LPS of the individual subgroups was revealed in passive haemagglutination inhibition reaction (PHAIR). Partial cross activity was clearly demonstrated in immunoprecipitation experiments in the five subgroups. Serological properties of the LPS of P. aeruginosa 03 subgroup essentially correlate with the structure of their polysaccharide chains determining O-antigenic specificity.

[Determination of in vivo and in vitro toxin activity. I. A new method of determining in vitro activity]. / Opredelenie aktivnosti toksinov in vivo i in vitro. Soobshchenie I. Novyi metod opredeleniia aktivnosti in vitro.

The potency of 5 toxins of different microbial species has been studied by common in vivo methods and by the in vitro method based on measuring the relative test-microbe growth inhibiting units 50. The possibility of using this method for the determination of toxicity in vitro with a view of studying the potency of diphtheria and gas-gangrene exotoxins, as well as that of Pseudomonas aeruginosa exotoxin, is substantiated.