Alkylation of poly(4-vinylpyridine) with methyl iodide for 12 h led to synthesis of the anionite poly(N-methyl-4-vinylpyridinium iodide). Iodination of an aqueous solution of the reaction product with an equimolar quantity of iodine in ethanol produced poly(N-methyl-4-vinylpyridinium triiodide) at quantitative yield. The structure of this compound was confirmed by UV, IR, and 1 H NMR spectroscopy and potentiometric titration. The antimicrobial activities of the compounds synthesized here are presented.

континентальные завозы холеры из региона Карибского бассейна (Кубы) и Азии в Америку (Канаду) и Европу (Великобританию, Италию, Бельгию и Германию) остаются основными эпидемиологическими рисками в распространении инфекции на глобальном уровне. В 2015 г. выявлена 21 эндемичная по холере административная территория в восьми странах Африки, Америки, в регионе Карибского бассейна и в Азии. Эпидемиологические осложнения обусловлены в основном V. cholerae О1 биовара El Tor, продуцирующими холерный токсин классического типа, а также V. cholerae O1 биовара Classical и V. cholerae О139 серогруппы. Эпидемические проявления холеры в России характеризовались завозами инфекции российскими гражданами, возвратившимися из-за рубежа; выделением из поверхностных водоемов V. cholerae О1 биовара Эль Тор ctxA-tcpA-, ctxA-tcpA + и V. cholerae О139 ctxAи tcpA-, а также единичных V. cholerae О1 биовара Эль Тор ctxA + tcpA +. Прогноз по холере на глобальном уровне и в России на 2016 г. остается неблагоприятным.

Sequencing of the cef (CHO cell elongating factor) gene of Vibrio cholerae serogroup O139 revealed one nucleotide substitution (T to C at nucleotide 2015) as compared to cef of classical V. cholerae O1 and two substitutions (GT to AC at nucleotides 2014-2015) as compared to cef of V. cholerae O1 El Tor. A comparative bioinformatic analysis showed that the substitution determines a threonine residue in position 672 of the Cef protein, while this position is occupied by an isoleucine residue in the classical strains and a valine residue in the El Tor strains. The latter two amino acids are hydrophobic, while threonine is hydro philic, having a polar R group. The nonsynonymous substitution affects the predicted secondary and, prob ably, tertiary structures of the Cef O139 protein and explained our previous finding that the protein fails to degrade tributyrin, while retaining the tweenase activity spectrum and all other characteristics. It cannot be excluded that the inability of Cef O139 to cleave triglycerides, along with other genetic specifics, contribute to the fact that the O139 serogroup has been supplanted from a dominating position in etiology of cholera by the El Tor biotype. The nucleotide sequence of the V. cholerae O139 cef gene and the deduced amino acid sequence of its product are reported for the first time and were deposited in GenBank under accession nos. JF499787 and AEC04822.1, respectively.

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Background. The problem of cholera remains acute for world health service and risks of importation of Vibrio cholerae strains from endemic countries to Russia do exist. Toxigenic strains (carrying cholera toxin genes ctxAB) can cause epidemic outbreaks of cholera and non-toxigenic (ctxAB-) – single or multiple cases of cholera-like diarrhea. Investigation of their ability to survive in water reservoirs in climatic conditions of middle latitudes by means of forming biofilms is essential for potential threat evaluation. Materials and methods. Biofilm formation by 15 V. cholerae strains on abiotic surfaces was studied in microcosms with tap water and cover glasses. Identification of responsible genetic determinants in whole genome sequences and bioinformatics analysis were performed using BioEdit 7.2.5, BLASTN 2.2.29, Blastp and Vector NTI Advance 11 software. Results. The strains investigated differed in terms of biofilm formation which correlated with structural features of genes for MSHA pili (msh), matrix polysaccharides (vps) and proteins (rbm) as well as for certain regulatory factors. Strains with none or few genetic deviations from prototypes formed mature biofilms in 5-7 days while those containing truncated genes mshL, mshN, rbmC – only in 13 days. One strain with truncated gene for positive regulator vpsR formed an immature biofilm. Acceleration of the process in some strains up to 2-3 days correlated with either truncated gene hapR (negative regulator) or altered structure of both msh and vps-rbm gene clusters. Conclusion. Analysis of genetic determinants responsible for biofilm formation may be used for prediction of V. cholerae ability to survive in environmental objects of Russia and thus the potential danger of the latters as sources of infection.