Department of Extremophilic Microorganism Biology

The Department was founded in 1965 and over 35 years was headed by Yurij Malashenko, Corresponding Member of the National Academy of Science of Ukraine. The main scientific directions of the Department were fundamental and applied researches of methane-oxidizing bacteria. Since 2005 the Department is headed by Dr. Oleksandr Tashyrev and activities of the Department are expanded to studying of extremophilic bacteria.

Recently the Department possesses 3 research directions:

Extremophilic bacteria

Researches in this area cover extremophilic bacteria of natural and man-made environment – Western Antarctica (primitive soils, freshwater lakes, rock cliffs, etc.), Negev Desert, rock cliffs of the Dead Sea (Israel), karst caves (Ukraine), hypersaline lakes (Bulgaria), sediments of the Black Sea, research nuclear reactor (Institute of Nuclear Research, Kiev, Ukraine), Chornobyl Nuclear Power Station buildings and soils of the alienation zone. The study of extremophilic microorganisms concerns their ecology, biodiversity, physiology, taxonomy, resistance to extreme environmental factors (γ-radiation, UV-lights, toxic metals, low temperatures etc.) and their potential biotechnological properties. On Antarctic island Galindez the Department possesses 2 research polygons – (multi landscape and rock cliff) for studying unique properties of microorganisms and their role in biogeochemical cycles. It is established, that copper-resistant microorganisms are widely occurred in Antarctic Region. In terrestrial biotopes (rocks, sludge, mosses, lichens, soils) of Galindez island and also in soil-like substrata of the Argentina archipelago islands and coastal area 30х60 km of the continent Antarctica the number of microorganisms, resistant to 100-1000 ppm Cu2+ makes 105-107 CFU/g of sample. A separate direction of the department is bioprospecting - targeted searches in extreme ecosystems of microorganisms possessing biotechnological properties. Using bioprospecting approach during 10 years was developed a collection of extremophilic microorganisms with unique properties (bacteria and yeast). It includes microorganisms resistant to 100-50 000 ppm of copper, chromium, cadmium, nickel and mercury ions, UV-resistant yeast that are hyper producers of melanin and carotenes (10-12% from total cell mass) etc. At present the collection is constantly updated. During 2008-2011 the Department participated CAREX Project (www.carex-eu.org) tackled the issues of enhancing coordination of research on life in extreme environments in Europe.

Development of microbial technologies

The Department carries out researches on biofuel production (low-molecular alcohols, methane and hydrogen) from organic waste. This includes both fundamental studies on metabolic pathways, the efficiency of biofuel synthesis and applied biotechnologies. Different modifications of the biotechnology showed high efficiency towards transforming waste to energy:

  1. mixed solid vegetable waste– fermentation cycle duration – 7 days, destruction rate 94%, hydrogen yield 80 litres per kg of dry waste;
  2. mixed culinary waste – fermentation cycle duration – 5 days, destruction rate 96%, hydrogen yield 48-50 litres per kg of dry waste;
  3. liquid starch waste – fermentation cycle duration - 5 days, destruction rate 97%, hydrogen yield -190 litres per kg of starch.

Basing on method for predicting the thermodynamic interaction of microorganisms with xenobiotics (synthetic organic compounds, toxic metals and radionuclides) there was developed a series of environmental biotechnologies. The core of technologies is mixed microbial communities produced granular form called microbial biocatalyst. Granulated biocatalyst provides effective purification of environmentally hazardous industrial waste water from the main classes of xenobiotics.

During 10 years there were obtained positive results of pilot scale testing and of various modifications of microbial biocatalytic technologies:

  • Complete treatment cycle liquid radioactive waste water of special nuclear research reactor and special laboratory "A" class of the Institute of Nuclear Research (INR)
  • Plant of municipal engineering "Kommash" – purification of metal-containing electroplating wastewater;
  • Complete degradation of solid food waste of Ukrainian Antarctic station "Academik Vernadsky" during wintering.

Methane-oxidizing bacteria

Studying methanotrophic bacteria as the biocatalytic systems that assimilates methane from atmosphere soil and water using in silico methods resulted new knowledge which concerns the role of methanotrophic bacteria in carbon cycle, the activity of the processes of methane-oxidation and methane-generation in natural ecosystems, mathematical models of atmospheric gases drainage into the hydrosphere; methane diffusion in limnetic reservoirs, etc. Philogenetic classification of metylotrophic bacteria gained international recognition; some strains are presented in international collections (ATCC, NCIMB). Fundamental research on ecology, taxonomy, physiology and biochemistry of methanotrophic bacteria revealed principally new peculiarities: absence of substrate specificity, presence of electron transfer against the thermodynamic potential, ATP generation provided by oxidation of the mineral compounds, syntabolism phenomenon - possibility of microorganisms to assimilate non-growing substrata. Following from these applied directions are: microbial synthesis of polysaccharides on non-food substrata; production of biogas from the renewable sources; development microbial product for treatment alcoholic and drug addiction, development a collection of methanotrophic bacteria.

During many years, scientific organizational activities had been conducted at the International Union of Microbiological Societies (IUMS), Association of Theoretical and Applied Chemistry (ICE), IUMS’ sub-Committee The Protein of the Unicellulars (SSCP), National Committee of Ukraine on New and Renewable Energy Sources. The cycle of theses on biology of methane-oxidizing bacteria was awarded with Zabolotny Prize (Yu. Malashenko, V. Romanovska).