Advances in research on signal molecules regulating biofilms
Bacterial biofilms (BFs) are membrane-like structures formed by the secretion of extracellular polymeric substances (EPS) by bacteria. The formation of BFs contributes to bacterial survival and drug resistance. When bacteria proliferate, they produce secondary metabolites that act as signaling molecules in bacterial communities that regulate intracellular and cell-to-cell communication. This communication can directly affect the physiological behavior of bacteria, including the production and emission of light (bioluminescence), the expression of virulence factors, the resistance to antibiotics, and the shift between planktonic and biofilm lifestyles. We review the major signaling molecules that regulate BF formation, with a focus on quorum-sensing systems (QS), cyclic diguanylate (c-di-GMP), two-component systems (TCS), and small RNA (sRNA). Understanding these processes will lead to new approaches for treating chronic diseases and preventing bacterial resistance.
KeywordsBiofilm Signal molecule Quorum-sensing Two-component systems
We are grateful to Prof. Daniel Grenier for critically read and corrected the manuscript. This work was supported by the National Key Research and Development Program of China (2018YFD0500100), the National Natural Science Foundation of China (31772761), the Henan Natural Science Foundation (182300410047).
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