One of central problems of modern biochemistry is the study of molecular mechanisms of cell adaptation, which is aimed at rebuilding its metabolism according to the conditions of environmental factors. The search for substances that are capable to protect and restore the biological activity of microorganism cells of industrially significant strains under long-term storage conditions, is an urgent task. The rapid development of technologies applied to synthesis of nanomaterials, in particular nanoparticles of metals (NPMe), allows significantly expand the limits of their use.
It is known that the activity of ATPase, subunits of which are exposed both to the cytoplasm and to the external environment, along with respiratory activity is one of the main physiological reactions of the bacterial cell that are the integral parameters of energy metabolism and cellular activity under the action of aggressive environmental agents.
Therefore, the purpose of this paper is to determine the level of activity of the membrane- bound ATPase and the specific respiratory activity of bacterial cells production strains under the influence of pre-cultivation in the presence of NPMe and after lyophilization/rehydration. In this paper, periodic cultures of bacterial cells of production strains have been used: Salmonella spp. . S. enteritidis 34 and M, S. dublin 12 and S.typhimurium 16 and Pasteurella spp. . P. multocida 5, 15, 396, 606, 877 and 1718.
During cultivation of bacterial cells of the experimental strains before the lyophilization/ rehydration step, colloidal dispersions of nanoparticles of Aurum (NPAu) and Argentum (NPAg) an average size of which is ~30 nm and an initial concentration . 19.3 ƒÊg/cm3 and 86.4 ƒÊg/cm3 of metals, respectively (4:1), have been added to the standard nutrient medium under aseptic conditions and the temperature (37.0 } 1.0) o„R. Incubation time has been (30.40) min.
After a process of lyophilization/rehydration in bacterial cells, specific respiration activity (specific RA) has been determined and based on the level of endogenous O2 formation, in the total membrane fractions of cells (TMF) . the value of ATPase activity, comparing the indices in the gexperimentalh and gcontrolh samples.
According to the research results, it has been determined that the restoration of the structural and functional state of rehydrated P. multocida strains 5, 606 and 877 (NPAg) and 1718 (NPAu, NPAg) under conditions of preliminary cultivation in the presence of NPMe occurs with the participation of both integral indices of the energy transfer system – induction of membrane ATPase and enhancement of specific RA, which testifies the membranotropy of investigated nanoparticles and provides cryosurveillance of cell membranes of these strains.
The determined stimulation or absence of changes in the specific RA index in cells of the strains Salmonella spp. that have been under the influence of NPMe and inhibition of membrane ATPase may also be indicative of the active restoration of their physiological state, but also affect the initial state of the main structural components of cell membranes of lipids and proteins.
Changes in the activity of membranous ATPase, even under conditions of prior cultivation of NPMe, may be related to the direct effect of lyophilization/rehydration processes of bacterial cells, and obtained result is an indisputable fact of the individual effect of NPMe on the functional state of bacterial cells within the same taxonomic species.
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