Voyda Y. Phenotypical polymorphism and genetic plasticity of strains of Е. coli from various biotopes, and safety of their biological properties by cryoconcervation

Object of investigation: a degree of display of signs of pathogenicity in clinical isolates of E. coli from various biotopes, level of viability and stored of biological properties of these isolates of E. coli at the different methods of long-term storage. The purpose: complex research of phenotypical polymorphism and genetic plasticity of strains of E. coli from various biotopes and development of effective method of long-term storage of mobile genetic determinant. Methods of investigations: microbiological, molecular-genetic, physical and chemical, statistical. Equipment: microscope "Biolam", thermostat, autoclave, dry-heat closet, photocamera of "Canon", programmatic freezing of bioobjects "Crioson BV-6". As a result of complex research of plasmid type, factors of pathogenicity and antibiotic susceptibility is got new information in considerable heterogeneity of population of E. coli from various biotopes by the level of phenotypical polymorphism and genetic plasticity. The fact of different sensitiveness to the damaging action of freezing of plasmid strains of Е. сoli isolated from various biotopes is first set. It is proved that cryoconcervation is provided by stability of not only chromosomal genome but also plasmid. Protocol of the optimum mode of cryoconcervation of plasmid strains of Е. сoli from various biotopes is developed. The degree of implementation: methodical recommendations, scientific manual, into the curriculum universities in Ukraine. Branch of use: medicine (microbiology, cryobiology, infectious diseases).