Intestinal interplay of quorum sensing molecules and human receptors

Human gut is in permanent contact with microorganisms that play an important role in many physiological processes including metabolism and immunologic activity. These microorganisms communicate and manage themself by the quorum sensing system (QS) that helps to coordinate optimal growth and subsistence by activating signaling pathways that regulate bacterial gene expression. Diverse QS molecules produced by pathogenic as well as resident microbiota have been found throughout the human gut. However, even a host can by affected by these molecules. Intestinal and immune cells possess a range of molecular targets for QS. Our present knowledge on bacteria-cell communication encompasses G -protein-coupled receptors, nuclear receptors and receptors for bacterial cell-wall components. The QS of commensal bacteria has been approved as a protective factor with favourable effects on intestinal homeostasis and immunity. Signaling molecules of QS interacting with above-mentioned receptors thus parcipitate on maintaining of barrier functions, control of inflammation processes and increase of resistance to pathogen colonization in host organisms. Pathogens QS molecules can have a dual function. Host cells are able to detect the ongoing infection by monitoring the presence and changes in concentrations of QS molecules. Such information can help to set the most effective immune defence to prevent or overcome the infection. Contrary, pathogens QS signals can target the host receptors to deceive the immune system to get the best conditions for growth. However, our knowledge about communication mediated by QS is still limited and detailed understanding of molecular mechanisms of QS signaling is desired. (c) 2021 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved.

Automated summary

The human gut is in constant contact with microorganisms that communicate through quorum sensing (QS) system, which helps coordinate optimal growth, regulate gene expression, and influence immune responses. The diverse QS molecules produced by both pathogenic and resident microbiota impact the host's intestinal homeostasis, immunity, and ability to resist pathogen colonization. Host cells can detect and respond to QS signals to mount effective immune defenses, while pathogens can manipulate host receptors to evade the immune system and promote their own growth. Despite this complex interaction, our understanding of QS-mediated communication is still limited, and further research into the molecular mechanisms is needed.