Modern Trends in Analysis of Cholera Vibrios Metabolism and Nutrient Requirements

Modern insights into cholera vibrios physiology in different life conditions are considered in the review. Described are metabolic peculiarities of V. cholerae growing on nutrient media and in vivo, as well as in cholera patient organism, with special emphasis on alterations of pathogenicity factors synthesis at different stages of the disease. Considered is biofilm role in V. cholerae preservation in inter-epidemic period. Regulation of cholera vibrios growth is shown to depend upon environmental signals which shift metabolism and alter nutrient requirements

Analysis of Genetic Determination of <I>Vibrio cholerae</I> Tweenase Activity

Studied are Vibrio cholerae of different serogroups on the presence of cef (CHO cell elongating factor) gene and activity against tweens and tributyrin using HDS-agar, prepared on the basis of bakery yeast pancreatic digest. Determined is the fact that all cef-positive strains hydrolyze tweens 20, 40, 60, 80, 85 and all but toxigenic V.cholerae O139, hydrolyze tributyrin. In contrast, non-toxigenic cef-negative strains of O139 serogroup, are active only against the latter. Apparently, the tweenase activity of Vibrio cholerae is provided, partly, by Cef, and the ability to hydrolyze tributyrin is the result of combined activity of Cef and other ferments. Shown is the efficiency of HDS-agar application to determine these characteristics

Cholera Vibrios non-O1/non-O139 Isolated in the Process of Epidemiological Monitoring over Rostov-on-Don Water Basins and Drain Sewage System within the Period of 2009–2011

Studied have been biological properties of cholera vibrios non-O1/non-O139 circulating in the Rostov-on-Don surface waters and drain sewage system within the period of 2009–2011. Overwhelming majority of the isolates have been classified as typical ones in terms of their phenotype. However 90 strains (21 %) out of total 280 have been identified as atypical ones against agglu­tina­bility in the slide-agglutination and full-scale agglutination reaction to diagnostic cholera sera. Put forward are recommendations on performance of the differentiation between V. cholerae non-O1/non-O139 and V. cholerae O1/O139. Specified are predominant sero­groups of the strains which turned to be unchanged within the stated period (O16, O53, O76, and O67). Revealed is the strain genotype variability and low probability of virulence manifestations. Demonstrated is the futility of the blind gene- and serological typing of aquatic strains

Characteristics of the Epidemiological Situation on Cholera the World Over

Within the last decade increase in cholera morbidity rate in the world has been revealed (with due consideration to linear trend). For 2013 maintenance of the tendency is forecasted. Epidemics, outbreaks and importations of the infection have occurred in 109 countries around Asia, Africa, America, Europe, Australia and Oceania. Nosoarea has been expanding owing to inclusion of new administrative territories and countries into the epidemic process, some cases being registered for the first time during the seventh pandemic. Apart from the endemic territories in India and Bangladesh, formation of endemic foci in twelve African countries has been exposed, as well as continued dissemination of epidemic cholera, consecutive in time and spatially stepwise. These facts testify of the follow-up of the seventh pandemic. Moreover, V. cholerae O1 El Tor strains with classical ctx-B allele have been spreading worldwide, which coupled with factors mentioned above predetermines unfavorable cholera forecast on the global level

Stabilized Phase Variants of <I>Vibrio cholerae</I> El Tor P-18895

Produced have been stabilized phase variants of V. cholerae El Tor P-18895 (O- and rugose colonies). Frequency of reversion to initial ST-phenotype does not exceed 10 %. Identity of the origin is verified in VNTR. Evaluated has also been their activity by means of the following diagnostic tests: agglutination assay, sensitivity to diagnostic bacteriophages test, and studies of growth behavior in solid nutrient media. Stabilized variants of V. cholerae El Tor P-18895 can be deployed for further investigations of peculiarities of biofilm formation on various surfaces, bacterial resistance to environmental factors, and for the enhancement of methods for isolation of cholera vibrio variants from ambient environment

Results of Application of the New Nutrient Media Set for Cholera Diagnostics within the Frames of the Special Tactical Training Exercises for Specialized Anti-Epidemic Team

Carried out is approbation of the new nutrient media set for cholera diagnostics on the basis of bakers' yeast pancreatic digest within the frames of the special tactical training exercises for specialized anti-epidemic team (SAET). It is demonstrated that the developed nutrient media set compare favourably with its analogues, commonly used for practical procedures; and its constituent media have a potential to be included into the SAET mobilization reserve

Evaluation of Biological Properties of New Selective Differential Medium for Cholera Vibrios Isolation Based on the Results of Laboratоry Trials

Previously developed selective differential medium for V. cholerae growth was modernized. The modernized medium called SDMV-M was shown to possess the required sensitivity and germination index. The growth of E. coli was entirely inhibited, that of P. vulgaris was inhibited considerably. The medium possessed good differentiating ability: orange V. cholerae colonies were clearly distinguished from concomitant microorganisms. In the laboratory trials SDMV-M demonstrated some advantages as regards V. cholerae isolation from contaminated faeces in comparison with the reference medium TCBS

Cholera in the Early XXI Century: Global Prognosis

The prognosis for cholera on 2011 proved true: the tendency of morbidity growth remained in the last decade (2002-2011) worldwide. Imported cholera cases caused large outbreaks and epidemics in the Caribbean countries and Asia. Formation of endemic foci in a number of countries of Asia and Africa took place, where favorable conditions for epidemics development (environmental and social conditions, military conflicts, economical and political instability) existed. Wide spread of genetically altered V. cholerae eltor and V. cholerae O139 variants with epidemic and pandemic potential was observed. All the events mentioned above predetermine the unfavorable prognosis for cholera on a global level

EVALUATION OF NUTRIENT MEDIA TO GROW SOME INFECTION DISEASES CAUSATIVE AGENTS

The detection methods for microbial agents that have epidemiological significance are diversity but cultivation on nutritional media remains the gold standard in microbiological diagnostics. Choice of medium depends on the conditions in which, bacteria were early and is present. The nature life determines its physiological peculiarity then a metabolic plasticity promote to survive and to save the virulence. In. this review on the example of Yersinia pestis and Vibrio cholerae performed evaluations of the efficient decisions for the bacterial media development. It is declared advantage of baker’s yeast hydrolisate as the nutrition media base

STUDY OF COMPOSITION OF PLANT EXTRACTS, POSSESSING ANTIMICROBIAL EFFECT AGAINST VIBRIO CHOLERAE EL TOR, USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

Aim. Study the composition of plant extracts using high-performance liquid chromatography (HPLC) and evaluation of their antimicrobial effect against Vibrio cholerae El Tor. Materials and methods. Qualitative and quantitative composition of plant extracts was studied using HPLC. Determination of sensitivity of microorganisms to plant extracts was carried out by diffusion into agar method and serial dilutions method. Results. Antibacterial effect of water, water-alcohol and acetone extracts of roots of Limonium gmelinii L., Berberis vulgaris L. and Glycyrrhiza glabra L. was studied. The most effective methods of extraction of biologically active substances, possessing antimicrobial effect against various strains of V.cholerae El Tor, were determined. Conclusion. The use of HPLC allowed to establish the presence of catechines, alkaloids protoberberines and glycyrrhizic acid in extracts, possessing antimicrobial effect against V.cholerae El Tor strains