Biomics

The ability of bacteria to adapt in conditions of intense interspecific competition and environmental stress is determined by the implementation of cellular response mechanisms. These adaptive reactions are based on a complex system of intracellular regulation, with about 6% of regulatory proteins containing enzymatic domains involved in the metabolism of the cyclic guanosine monophosphate dimer (c-di-HMP). This article systematizes modern ideas about the molecular mechanisms of biofilm formation of soil bacteria of the genus Pseudomonas with the participation of the Wsp system, where c-di-GMF acts as a key regulator of this process. Special attention is paid to the study of the influence of abiotic factors (SDS, ethanol, sodium chloride, glycerin, lysozyme, and carbenicillin) on the activation of the Wsp signaling pathway and the regulation of biofilm formation. It has been established that c-di-GMF controls the transition of bacteria from the planktonic state to the biofilm form, and also stimulates the synthesis of exopolysaccharides and adhesins. It has been shown that various abiotic factors have a significant effect on the activation of the Wsp system and can both stimulate and inhibit the biofilm formation process. New aspects of the regulation of bacterial populations through changes in the concentration of c-di-HMP are indicated: the role of the recently discovered genetic switch hecR-hecE, which is expressed bimodally, and is also involved in the formation of functionally different subpopulations and maintaining a balance between proliferation and colonization of P. aeruginosa surfaces, is demonstrated. The results of the review demonstrate the significant scientific potential of research into biofilm formation mechanisms and open up new horizons for the development of effective biological products aimed at increasing crop productivity, optimizing their growth parameters and increasing resistance to abiotic stress factors. This is especially important in the context of modern challenges related to the need to increase the efficiency of agricultural production and protect plants from adverse environmental conditions.

biofilms, Pseudomonas, c-di-GMF, Wsp-system, hecR, hecE

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