SPORE FORMING BACTERIA ISOLATED FROM ATMOSPHERIC AEROSOLS IN SOUTHWESTERN SIBERIA DURING ATMOSPHERIC TRANSFER OF AIR MASSES

Monitoring of near-surface and high-altitude samples of atmospheric aerosols has been performed on the territory of Novosibirsk region since 1998. This study presents the diversity and enzymatic activity of spore-forming bacteria isolated in the autumn of 2016 from high-altitude and near-ground samples obtained during monitoring of viable microorganisms in the atmospheric aerosols of Southwestern Siberia. A significant predominance of spore-forming bacteria over representatives of other microorganism groups was recorded during this period. This phenomenon might have been caused by a typical for the studied region influence of the southwestern wind, which carries dust particles from the steppes and deserts of Central Asia. These particles are usually contaminated with a large number of endospore forming bacteria. Biochemical and physiological features of the isolated spore forming bacteria were studied, their genomic identification was performed, and their enzymatic activity was determined. Based on the combination of phenotypic properties and genomic analysis of data, the obtained cultures were identified as belonging to the genera Bacillus, Paenibacillus, Brevibacillus, Lysinibacillus, Oceanobacillus and some others. The following species were identified among the representatives of the genus, i.e. Bacillus: B. beringensis, B. boroniphilus, B. cereus, B. firmus, B. korlensis, B. pumilus, B. thuringiensis, B. subtilis, B. brevis . The isolated spore-forming bacteria included strains with high amylolytic, proteolytic, lipolytic and nuclease activity They are capable of utilizing fatty acid esters, solid fats, oils and petroleum products. The most productive lipase producers were bacteria of the genus Lysinibacillus capable of fermentation at pH 5.0-9.0. Strains secreting high levels of the tested enzymes may be useful for biotechnological application.