Department of General and Soil Microbiology

The Department of General and Soil Microbiology was founded in 1929. The first Head of the Department was Academician M. Kholodny, a world-known scholar. During the pre-war years A. Rokytska and M. Bohopolsky were the Heads of the Department; Prof. L. Rubenchik, Corresponding Member of the National Academy of Science of Ukraine was in 1948 – 1968; Prof. K. Andreyuk, Corresponding Member of the National Academy of Science of Ukraine was in 1968 – 1993. Prof. G. Iutynska, D.Sc., Corresponding Member of the National Academy of Science of Ukraine has been the Head of the department since 1993.

Prof. L. Rubenchik and K. Andreyuk together with the leading scientists O. Bershova, V. Smaliy, and Kh. Zinovyeva founded the following two scientific schools that have successfully been developing since then: ecological-physiological research of soil microflora and biogeochemical activity of microorganisms.

In the 1950 – 1960’s the scholars’ main attention was focused on the research of some groups of microorganisms (mycobacteria, cyanobacteria, actinomycetes and nitrogen-fixing bacteria) and interrelations between soil microorganisms and plants. An important role of rhizospheric microorganisms in providing plants with biologically active compounds (B group vitamins, heteroauxins, free aminoacids, etc.) was established.

fade

Nowadays, within the interrelations between soil microorganisms and crops, a special attention of our Department’s activity is focused on a research of natural formation and increase of the activity of microbial-plant symbiotic systems. Furthermore, a lot of attention is given to a selection of active strains of nitrogen-fixing, phosphor-mobilizing microorganisms as the basis of complex polyfunctioning agents for plant growing. Some peculiarities of interrelations between rhizobia and leguminous plants at early stages of their symbiosis have been studied. The effect of phyto-regulating compounds (flavonoids, phytohormones, plant growth regulators) upon the physiological properties of root nodule bacteria has been researched. So far, it has been shown their activity in nano- and picomolar concentrations which launches a cascade system of physiological reactions of rhizobia such as: their growth activity, biomass accumulation; increase of exopolymers production; as well as increasing the activity of main ammonium assimilation enzymes (glutamine synthetase, glutamate dehydrogenase). In our Department a collection of nitrogen-fixing microorganisms (approx. 300 strains) is created, among them there are some representatives of azotobacter species, and root nodule bacteria of soya, pea, alfalfa, goat’s-rue, melilot, fodder beans, etc.

The Department’s leading researches about streptomycetes ecology, physiology and taxonomy are widely-known in Ukraine and beyond it. A collection has been created from streptomycetes isolated from different soils in Ukraine, Russia, Belarus, Georgia, Armenia, Azerbaijan, Germany, and even from the Antarctic soil-substrata. The collection of over 3,000 strains is constantly enlarged and is the selection source for producers of a broad range of biologically active compounds. A selected strain of Streptomyces avermitilis УКМ Ас-2179 is a competitive producer of an avermectine complex and biologically active compounds such as: lipids, aminoacids, B group vitamins, auxins (indolylacetic acid), cytokinins (isopenthyladenine, zeatine, zeatine-rhybozid), and gibberellic acid. The complex called Avercom, is active against nematodes, stimulates plants growth, is untoxic and ecological safety and is quite promising for the development of a polyfunctioning preparation with nematocidal and phyto-stimulating activity.

Based on long-term researches, a new methodological approach in soil microbiology has been developed. According to it, a microbial community is considered to be a sophisticated hierarchical self-regulating system which has certain taxonomic and functional structures. The usage of mathematical analysis and IT gives the opportunity to improve the system approach of soil microbiota research. A new mathematical model for a forecast and regulation of the state of soil microbial cenosis under different ecological conditions has been created. A hierarchical system of bioindication indices for the soil microbiological monitoring has been developed.

The new scientific doctrines to improve the functions of microbial communities and the ecological conditions and increase the soil fertility have been developed. Considering the above mentioned problems some issues of soil protection are analyzed. Some strains of microorganisms which are active destructors of the pesticides have been selected. The strains are as a component in biotechnology for soil remediation.

The above fundamental studies became the basis for the development and for industrial implementation of new microbial preparations. Some efficient strains of nitrogen-fixing, phosphor-mobilizing microorganisms are the main compounds of the ecologically safe bacterial preparations Nitragin and Rhizobin (on the basis of nodule bacteria), Ecoriz (on the basis of Rhizobium radiobacter), Ecovital (on the basis of nodule bacteria and Bacillus megaterium), Ecophosphorin (on the basis of Rhizobium radiobacter and Bacillus megaterium).

Another area of the Department’s activity is to study biogeochemical activity of soil microorganisms. It started to develop actively at the end of the 1960’s as a solution of a critical situation (formation of sulfuric acid), which rose up while the tunnel construction for the Kyiv Underground. It was stated that the phenomenon was caused by active development of tionic bacteria oxidized sulphur compounds to sulfuric acid. Within the corrosion researches special attention is paid to technogenesis. Its influence is spread on thousands kilometers of gas pipe-lines, communication cables, construction of underground reservoirs, tunnels etc.

On the basis of broad ecological-physiological, microbiological, biochemical and electrochemical studies, fundamental regulations were created to forecast or eliminate the corrosion situations on these constructions. The soil aggression criterion was estimated by including microbiological, chemical and electrometrical soil indices. An express test to estimated bacterial aggression assessment was offered on the basis of the exopolymers corrosive activity.

The Department was first to reveal the specific zone (ferrosphere) characterized by increase of the microorganisms’ biological activity in direct proximity of a metallic construction. In the ferrosphere, in its turn, a biofilm formed on the metal surface was isolated where the bioelectrochemical processes of metal ruination took place. An oxidizably dangerous microbial communities was shown to form on the metal surface or cover the biofilm whose architectonics was formed by iron-deficiency and sulphur-enriched sulfides and exometabolites of the microorganisms dominated by sulfate- reducing bacteria.

Various means of anticorrosion protection is studied, among them there are insulating coverings and corrosion inhibitors. Determination of the bioresistance of modified oil-asphalt and organic-silicon biocide-containing materials made it possible to recommend reliable coverings. High-molecular cationic surfactants were established to be the most efficient corrosion inhibitors. The protective activity of the inhibitors was considerably caused by the fact that these compounds were adsorbed on the metallic surface forming a protective film that inhibited the process of hydrogen-formation on the steel surface, thereby promoting decrease of bacterial catalytic and corrosive activity.

The scientific results of the Department’s team have been generalized in 30 monographs and study manuals, over 300 articles and industrial guidelines; 20 patents; 4 State Standards of Ukraine, and the CIS State Standard. The Department’s scholars have defended 6 doctorates and 35 candidate dissertations. Three members of the staff were elected Corresponding Members of the Academy of Science of Ukraine; another one was rewarded with the title of the Honorary Scientist; 6 were awarded with Ukraine’s National Academy’s Zabolotny Prize; 3 – with the Prizes of the Presidents of the Academies of Sciences of Ukraine, Belarus and Moldova; and 2 – with the Prize of the USSR Council of Ministers.