Quorum sensing in Gram-negative bacteria: signal molecules, inhibitors and their potential therapeutic application

Abstract

Quorum Sensing (QS) is a phenomenon of chemical cell-to-cell communication consisting in the synthesis and secretion of signal molecules called autoinducers into the environment, which contribute in regulation of various physiological processes. QS was identified in different bacterial species, including symbiotic and pathogenic bacteria. QS systems play a crucial role in regulation of expression of genes which control motility, biofilm formation, and synthesis of virulence factors by pathogenic bacteria. These systems recognize signal molecules of different specificity which belong to a few groups and enable intra- and interspecific communication of bacterial cells as well as communication with cells of eukaryotic organisms (hosts). Inhibition of QS called Quorum Quenching (QQ) is now regarded to be a promising strategy to combat bacterial infections. So far, a large group of substances of natural and synthetic origin with a function of QS inhibitors, which can have potential therapeutic applications, has been identified.