Formation of resistance to the disinfectant drug “Dezaktin” in mycobacteria
The purpose of the work was to study the resistance formation in mycobacteria at multiple passages in the presence of the disinfectant “Dezaktin”, to compare the critical concentrations of “Dezaktin” at repeated and single exposure, as well as depending on the phase of growth of the seed. Under the conditions of the constant effect of “Dezaktin” on mycobacteria, it has been established that the mechanisms of resistance formation in pathogens and saprophytes have different paths. The adaptive response of pathogens of tuberculosis and paratuberculosis to adverse conditions in vitro is similar to the process that occurs in vivo and was characterized by transformation into dormant and CWD-forms. The mechanism of resistance in M. phlei to “Dezactin” consisted in the formation of heteromorphic populations with a partial or complete loss of acid resistance, thickening of the cell wall, and an increase in adhesive and hydrophobic properties. M. phlei had the highest biocide resistance, and MAP among pathogenic cultures. After 13 consecutive passages, the critical concentration of “Dezactin” in the medium for M. bovis and M. avium increased 100 times, for MAP — 7, for M. phlei — 1.4 times. The research results allow us to conclude that the processes of adaptation of pathogenic and saprophytic mycobacteria to the negative effects of the environment have different paths, which, in our opinion, is due to the evolutionary niche of their existence, namely, the first group are intracellular parasites, and others are environmental mycobacteria