Conclusion: The purification protocol based on the combination of tangential flow filtration and two steps of ultracentrifugation, one of them through the sucrose gradient, was the most efficient for obtaining high concentrated, non-aggregated virus suspension suitable for XFEL studies.

A new low-basicity functional detergent, namely, 1-methyl-3-hexadecyl-2-(oximinomethyl)imidazolium bromide (pK a = 7.74) is proposed for the efficient decomposition of acyl-containing ecotoxicants under mild conditions (pH » 9.0). The use of this compound provides for rapid decomposition of model substrates, namely, 4-nitrophenyl esters of diethylphosphonic, diethylphosphoric, and 4-toluenesulfonic acids. The title compound is not less efficient than high-basicity supernucleophilic functional detergents with pK a ³ 10.0.

Вирус клещевого энцефалита (ВКЭ) является возбудителем тяжелого неврологического заболевания человека и широко распространен на территории Евразии. При репродукции флавивирусов помимо инфекционных вирионов накапливается набор неинфекционных вирусных структур: незрелые формы вирионов, пустые формы (не содержащие геном вирусные частицы), а также агрегаты поверхностного белка Е, способные оказывать влияние на иммунный ответ, и патогенез. Штаммы ВКЭ могут различаться по соотношению этих форм в инфекционном материале, т.е. по характеру структурной гетерогенности. Цель: подобрать комплекс методов, способных выявить данные различия. Методы. Общую концентрацию белка Е определяли методом ИФА, число частиц, содержащих геном (ГСЧ) - ПЦР в реальном времени, а для выявления инфекционных вирусных частиц - титрование в культуре клеток. Результаты. Разработан метод оценки структурной гетерогенности популяции ВКЭ. Было показано, что повышенное содержание неинфекционных вирусных частиц, содержащих геном, и несвязанных с ними белка Е не зависит от подтипа вируса. Выводы. Штаммы ВКЭ отличились по соотношению общего числа ГСЧ к числу инфекционных вирионов и по содержанию белка Е, связанного и несвязанного с ГСЧ. Tick-borne encephalitis virus (TBEV) is widespread in Europe and Asia and causes severe neurological disease in humans. It has been established that the reproduction of flaviviruses leads to the accumulation of a whole set of non-infectious viral structures aside from infectious virions. These structures include immature virions, empty forms (containing no genome) and aggregates of the surface protein E. These structures, despite being non-infectious, are able to influence the immune response and, consequently, the pathogenesis of TBEV infection. The aim of this work was to select a set of methods which can be implemented to identify these differences. Methods. Virus samples were analised for protein E concentration, number of genome-containing particles and infectivity. The total concentration of protein E in samples was evaluated using ELISA. The number of genome-containing particles was determined by a real-time PCR, and to assess the number of infectious virus particles titration in PEK cell culture was used. Results. An assay for total concentration of protein E in culture fluid of cells infected with different strains of TBEV based on the commertially available ELISA kit was developed. TBEV strains used in the study varied by the ratio of genome-containing particles to infectious virions. The amount of protein E not associated with genome-containing virions was calculated as a difference between total content of protein E and the amount of protein E bound to genome-containing particles. This amount was also different for studied samples of TBEV strains. Conclusion. No correlation was observed between the increased content of non-infectious genome-containing particles or the amount of residual protein E and TBEV subtypes.

The reactivity of a series of micelle-forming 1-alkyl-3-(1-oximinoethyl)pyridinium bromides in the cleavage of typical acyl substrates was studied and analyzed. The nucleophilicity of the functional surfactants does not change significantly upon variation of the length of the alkyl chain. The differences in the observed rates of cleavage of the model substrates are attributed to differences in the hydrophobic properties of the surfactants.Functional surfactants (FS) are a unique type of reagents. Upon dissolution in water in amounts exceeding the critical micelle concentration, these compounds combine in supermolecular ensembles with a functionalized surface, on which the concentration of the reactive groups will be maximalized for such systems [1][2][3]. This feature of functional detergents permits anomalously high rates of acyl group transfer reactions, while systems derived from such detergents hold considerable promise as agents for the efficient cleavage of acyl substrates and, especially, of highly toxic esters of phosphoric and phosphonic acids [1,2].The micellar effects of such organized molecular systems depend on a host of factors but primarily on 1) the change in the properties of the medium upon transferring the reaction from water to the micellar pseudophase and 2) concentration of the substrate in the surfactant micelles [1-6]. The first factor may lead to change in both nucleophilicity and the acid-base properties of the functional group [4,5]. The differences in the activation free energies for reactions in micelles of functional detergents or functional/cationic surfactant comicelles and in water are negligibly small, as indicated by data for a series of functional surfactants and comicelle systems [4][5][6][7][8]. The second factor involving concentration of the substrate in the micellar pseudophase, as a rule, plays the determining role in increasing the observed reaction rates relative to the rates for their structural analogs not forming micelles [4][5][6]9]. This property is directly linked to the hydrophobic properties of both the substrate itself and the functional detergent [4,[9][10][11]. These hydrophobic interactions are specifically responsible for transfer of the nonpolar electroneutral substrates from water into the surfactant micelles.In the present study, we analyzed the kinetic behavior and factors controlling the reactivity and micellar effects of 1-alkyl-3-(1-oximinoethyl)pyridinium halides (I-IV) in the cleavage of 4-nitrophenyl esters of diethylphosphonic (NPDEPS), diethylphosphoric (NPDEP), and 4-toluenesulfonic (NPTS) acids.