Abstract
The appearance of an array of data on the study of the intestinal microbiota in Metazoa has significantly expanded our understanding of the role of commensals in the control of a wide range of physiological functions in higher organisms in norm and pathology. In the intestine, where the microbial load significantly exceeds the number of microorganisms of other ecosystems, the components of the intestinal microbiota are a constant source of stimuli that induce activation of the host immune system. The introduction into practice of biomedical research of innovative high-resolution methods, including multi-omics technologies, has brought data that change our understanding of intestinal commensals, including probiotics with GRAS status, widely used in medicine, agriculture and biotechnology. The ability of these bacteria to induce negative processes in the host body that are beneficial for bacterial proliferation and expansion revealed a clear lack of our knowledge about the logic of their life and the mechanisms of interaction with eukaryotic cells. This determines the urgent need for comprehensive research of probiotics and the development of standardization of their safety assessment. Apriori's confidence in the exceptional benefit of the bacteria widely used in medicine, agriculture and biotechnology has determined the seriously omission in our control system today - the lack of standardization of studies for the safety assessment of bacteria with GRAS status . The moment has come when it became clear that this gap should be promptly filled and that only exact understanding the molecular base of interacting the microbes with eukaryotic cells can provide the foundation for effective practical developments in controlling the evolution of bacterial virulence and probiotic safety strategy, as well as the competent use of genetic technologies for monitoring the environment and managing infectious processes, thus avoiding the dramatic consequences of large-scale interventions in the micro and macro worlds.