[USE OF VIBRIO CHOLERAE SURFACE STRUCTURES FOR SPECIFIC PROPHY- LAXIS AND DIAGNOSTICS OF CHOLERA].

The need for efficient and cost-effective cholera vaccine hasn't lost its actuality in view of the emergence of new strains leading to severe clinical forms of cholera and capable to replace strains of the seventh.cholera pandemic, and in connection with the threat of cholera spreading beyond the borders of endemic countries. In this review data from literature sources are presented about the use of outer membrane proteins, vesicles, cell ghosts of the cholera causative agent in specific prophylaxis and diagnostics of the disease.

[N-ACETYL-ß-D-GLUCOSAMINIDASE OF VIBRIO CHOLERAE].

AIM: Study N-acetyl-ß-D-glucosaminidase (chitobiase) (EC 3.2.1.30) in strains of Vibrio cholerae of O1/non-O1 serogroups of various origin, that is a component of chitinolytic complex taking into account object of isolation and epidemiologic significance of strains. MATERIALS AND METHODS: Cultures of V. cholerae O1/non-O1 serogroup strains were obtained from the museum of live culture of Rostov RIPC. Enzymatic activity analysis was carried out in Hitachi F-2500 fluorescent spectrophotometer using FL Solutions licensed software. NCBI databases were used during enzyme characteristics. RESULTS: N-acetyl-ß-D-glucosaminidase in Vcholerae O1/non-O1 serogroup strains was detected, purified by column chromatography, studied and characterized by a number of physical-chemical and biological properties. Comparative computer analysis of amino acid sequence of N-acetyl-ß-D-glucosaminidases of V. cholerae (VC2217 gene), Serratia marcescens etc. has allowed. to attribute the enzyme from V. cholerae to glycosyl-hydrolases (chitobiases) of family 20 and classify it according to enzyme nomenclature as EC 3.2.1.30. CONCLUSION: N-acetyl-ß-D-glucosaminidase in V. cholerae of O1/non-O1 serogroups of various origin and epidemiologic significance, participating in chitin utilization was studied and characterized for the first time, and its possible role in biology of cholera causative agent was shown.

[VIBRIO CHOLERAE CHITINOLYTIC COMPLEX:THE COMPOSITION AND THE ROLE IN PERSISTANCE].

Reviewed the paper are the composition and functions of Vibrio cholerae chitinolytic complex which play an important role in the maintaining and creating new forms of vibrios in the environ- ment, it is better adapted to survive in environmental.

Characterization and classification of strains of Francisella tularensis isolated in the central Asian focus of the Soviet Union and in Japan.

The two subspecies of Francisella tularensis, F. tularensis subsp. tularensis (type A) and F. tularensis subsp. palaearctica (type B), differ from each other in biochemistry and virulence. Strains of F. tularensis subsp. tularensis are believed to be confined to North America, whereas strains of F. tularensis subsp. palaearctica occur in Europe, in Asia, and in North America. Moreover, the existence of two other subspecies, designated F. tularensis subsp. mediaasiatica and F. tularensis subsp. palaearcitica japonica, has been suggested for strains of F. tularensis isolated in the central Asian focus of the Soviet Union and in Japan, respectively. In the present study, strains biochemically classified as F. tularensis subsp. mediaasiatica or F. tularensis subsp. palaearctica japonica have been investigated by hybridization with probes specific to 16S rRNAs of the two main subspecies. Furthermore, the virulence and biochemical characteristics of the strains were compared with those of strains belonging to F. tularensis subsp. palaearctica and F. tularensis subsp. tularensis. It was found that 16S rRNAs of F. tularensis subsp. mediaasiatica and F. tularensis subsp. palaearctica japonica hybridize with the probe specific to a genotype proposed herein, genotype A (F. tularensis subsp. tularensis), which shows that strains genetically related to this subspecies are found outside North America. However, the central Asian strains differed from F. tularensis subsp. palaearctica and F. tularensis subsp. tularensis strains when investigated by fermentation of glucose. The results of the biochemical tests could not be unambiguously used for differentiation of strains into F. tularensis subsp. palaearctica or F. tularensis subsp. tularensis. These drawbacks suggest that classification of strains of Francisella on the basis of 16S rRNA analysis may be preferable to classification on the basis of biochemical analysis.

[Adenylate cyclase of the causative agent of plague: its purification and properties]. / Adenilattsiklaza vozbuditelia chumy: ochistka i nekotorye svoistva.

Three forms of adenylate cyclase have been detected in Y. pestis: membrane-bound, cytoplasmic and extracellular. Extracellular adenylate cyclase has been purified so as to achieve a homogeneous state, and some of its physicochemical parameters have been investigated. In the process of purification the initial preparation of this enzyme has been subjected to heating at 100 degrees C for 15 minutes, fractionation with ammonium sulfate, and gel filtration on Sephadex G-100. The homogeneity of adenylate cyclase has been confirmed by electrophoresis in 7.5% polyacrylamide gel and precipitation by the plague agglutinating serum. The enzyme has been found to have a molecular weight of 30,000 daltons and to show the optimum activity at pH 7.0-7.2 and at a temperature between 37 and 40 degrees C. Monospecific rabbit serum to the homogeneous preparation of adenylate cyclase has been obtained.

[Changes in the cathepsin activity of reticuloendothelial cells under the effect of biologically active substances]. / Izmenenie urovnia aktivnosti katepsina v kletkakh retikuloendotelial'noi sistemy pod vliianiem biologicheski aktivnykh veshchestv.

The level of cathepsin D, an enzyme of the lysosomal origin was used as a criterion of the increase in the digestive capacity of macrophages under the action of biologically active substances. It was shown that the use of prodigiosan changed the enzyme activity in the cells of the peritoneal exudate and spleen of the albino mice. Increased activity of cathepsin D was considered as a state of increased readiness for phagocytosis.