Experimental study of populations of pathogenic listeria in environment using scanning electron microscopy

Due to accumulated data, the ideas on existance and the state of pathogenic and opportunistic bacteria in different ecosystems gradually change, while distribution, adaptation, growth and development of bacterial forms in populations in different media and objects remain relevant. Listeria are known to be resistant to external factors, and the frequency of their transmission through plant production increses significantly. At that, the data concerning ecological aspects of living cycle of the pathogen are still limited. Ecology of the bacteria is one of the substantial sections of biology concerning development, survival and interactions of the microorganisms population and the environment. One of the perspective trends in studying ecology of the pathogenic bacteria is approach on population level being based on a study of bacterial colonies, and not a separate cell. The date of the experiments are presented in the paper being carried out with using scanning electron microscopy method resulting in ability to study bacterial colonier without violation of their natural architectonics. The morphological features of Listeria populations in the different objects of inhabitance medium, e.g. milk and meat products, feeds, water, green plants, in a broad temperature rang (from -18 up to 37 °С) were examined. Morphological plasticity of Listeria cells and the peculiarities of Listeria populatios existence in the environment were demonstrated on the presental scanogramms. It was shown that Listeria adapted to the changing conditions of existence acquiring the ability to transform into heteromorphism with the different manifestations of L-transformation resulting in their prolonged persistence in the environment. The obtained data allowed to reveal the main conformities of the survival rate of those bacteria. Specifically, heteromorphism concerns such mechanism with the different manifestations of L-transformation, as well as the ability to form the microcolonies and colonies by a type of multicellular organism, integrity of a population during a process owing to the interpopulations bonds, ability of a population to react onto influence of inhabitance medium. The data etended our ideas on the structure and functions of pathogenic organism. In a broad sense, it allows to revise a lot of practical problems concerning control of pathogens both in environment and in macroorganosm, including recommendations on desifectants, medicines, therapy and prophylaxy.