Cytotoxic effect of silver and oxide graphene nanoparticles on aberrant forms of Escherichia coli

Abstract

The acquisition of aberrant morphological variations by microorganisms can serve as a phenotypic manifestation of antibiotic resistance, which results from ad-aptation to growth in a potentially toxic environment. Therefore, morphogenesis should be considered as an adaptive process that makes a great contribution to the ubiquity and universality of prokaryotes. The aim of the research was to evaluate the antibacterial activity of silver and oxidized graphene nanoparticles on pheno-typically aberrant forms of Escherichia coli. As a result of research, it was found that the antibacterial activity of silver nanoparticles is significantly higher compared to that of oxidized graphene nanoparticles on pleomorphic varieties of Escherichia coli, as the minimum inhibitory concentration of silver nanoparticles is lower (13.1 µg/ml) than that of oxidized graphene nanoparticles (75.3-94.9 µg/ml). The mor-phological variance of E. coli correlated with the acquisition of antibiotic resistance by the bacterium, but was not accompanied by a simultaneous increase in resistance to the nanoparticles. According to the results of atomic force microscopy, the toxic effect of oxidized graphene nanoparticles at supratoxic concentrations on aberrant forms of E. coli did not differ from that on canonical forms of the bacterium and was expressed in the destruction of the bacterial population and filling the intercel-lular space with biomass of degraded bacterial cells.