Микробиология и вирусология 155 УДК 579.852.11:616.981.455; 577.151.45 А.в. корнева, в.б. Николаев, с.Н. козлов, Е.Ю. Марков, А.в. Мазепа, Ю.о. Попова выявление мембрАносвязАнных протеАз FRaNCISElla tUlaRENSIS ФКУЗ «Иркутский научно-исследовательский противочумный институт Сибири и Дальнего Востока» Роспотребнадзора, Иркутск, Россия Проведено исследование наличия протеолитической активности и состав протеаз в поверхностных структурах клеток шести штаммов Francisella tularensis разных подвидов. Препараты мембранной фракции возбудителя туляремии получали путем обработки микробной массы мочевиной. Субстратный электрофорез выявил три общих для всех штаммов полипептида, обладающих протеолитической активностью. У препаратов F. tularensis subsp. nearctica и F. tularensis subsp. novicida обнаружены дополнительные полосы протеаз. Ключевые слова: Francisella tularensis, субклеточные фракции, наружные мембраны, ферменты, протеазы протеолитическая активность dEtEction of mEmbranE-bound protEasEs of FRaNCISElla tUlaRENSIS Sterile preparations of membrane fractions were prepared by processing of live Francisella tularensis cells of different subspecies with 4.5 M urea solution and differential centrifugation. For the first time, proteolytic activity was detected and studied by tests of radial enzyme diffusion and substrate polyacrylamide gel electrophoresis using gelatin as a substrate. Spectrum of gelatinases in the resulted preparation were detected. Quantitative inter-strain differences in the protease activities and their qualitative composition in membrane preparations of various virulent F. tularensis strains was analyzed. Avirulent F. tularensis 21/400 subsp. holarctica (I-214) strain demonstrated the greatest gelatinase activity in enzyme diffusion method and the lowest hydrolytic activity was seen in F. tularensis B-399 A-Cole subsp. tularensis (I-386) and F. tularensis Utah 112 subsp. novicida (I-384), other preparations showed intermediate activity. Enzyme electrophoresis in the protease spectra determined the presence of proteins with proteases activity 50-100 kDa, and in the spectrum preparations of F. tularensis I-386 and I-384 were detected additional bands of proteases.

This paper is dedicated to an integrated environmental assessment of soil cover in the Ivanovo Region’s territory. Using modern instrumental methods of analytical control has been determined a content of gross and mobile forms for Pb, Cd, Co, Ni, Zn, Mn, Cu and Fe in the soil. The analysis of the soils ecological state in the period from 2010 to 2014 has been performed. It has been found that the region soils are generally characterized by relatively low levels of heavy metals contamination. Areas with high concentrations of heavy metals’ mainly mobile forms are local ones. For the first time in Ivanovo region has been performed an assessment related to potential risk of soil contamination for the public health. Comparison of experimental results with statistical materials on morbidity and mortality, as well as the subsequent analysis of the obtained data together with the results of sanitary-hygienic research allow highlight the most contaminated areas, and identify potential sources of negative impacts, as well as to conduct ecological and hygienic assessment for investigated region’s soil status. Using of vivid cartographical techniques allows visually assess the scale of contamination for Ivanovo region’s soil cover, and reveal this information to the public in a timely manner.

The advantages of vegetable oil-based biofuels using in diesel engines have been demonstrated. Methods for determining of optimal composition for mixed fuels containing petroleum diesel fuel and methyl ester of rapeseed oil have been proposed. Optimization calculations of such mixed fuel composition for a type 245.12С diesel engine have been carried out using the proposed methods. It has been shown that a mixture containing 60 % of petroleum diesel fuel and 40 % of methyl ester of rapeseed oil has the best ecological characteristics among the researched mixed biofuels. Even better ecological characteristics are reached when such mixture’s ingredients are regulated according to changes of the engine’s shaft rotation speed and load.

The article displays advantages of using multicomponent mixed biofuels for diesel engines, i.e. mixtures of oil diesel fuel and rapeseed oil, rapeseed oil methyl ester, gasoline. The results of experimental research on a D-245.12C type automotive diesel engine running on these fuels are presented. A method of determining the optimal composition of multicomponent biofuels is proposed. Using this method optimization calculations of the fuel compositions are made. It is demonstrated that among tested biofuels the mixture of 80% oil diesel fuel, 10% of rapeseed oil and 10% of gasoline possesses the superior ecological parameters.

The depletion of oil fields and the deteriorating environmental situation leads to the need for the search of new alternative sources of energy. Actuality of the article due to the need for greater use of the alternative fuels in internal combustion engines is necessary. Fuels produced from vegetable oils and animal fats as advanced alternative fuels for diesel engines are considered. These fuels are produced from renewable raw materials and are characterized by good environmental qualities. Advantages of using fuels of vegetable origin as motor fuels are shown. Experimental research of diesel engine D-245.12S functioning on mixtures of diesel fuel and mustard oil of various percentage is given. One of the most wide spread vegetable oils in Russia is mustard oil. Possible ways of using mustard oil as fuel for a diesel engine are considered. An opportunity of improving characteristics of exhaust gases toxicity by using these mixtures as a fuel for automobile and tractor diesel engines is demonstrated.