Links between S‐adenosylmethionine and Agr‐based quorum sensing for biofilm development in Listeria monocytogenes EGD‐e

• Published in: MicrobiologyOpen (Weinheim) Vol. 9; no. 5; pp. e1015 - n/a
• Main Authors: Lee, Yue‐Jia, Wang, Chinling
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01-05-2020; John Wiley and Sons Inc; Wiley
• Subjects: activated methyl cycle; Adenosylmethionine; Availability; Bacteria; biofilm; Biofilms; Biofilms - growth & development; Chemical synthesis; Dilution; DNA, Bacterial - genetics; Extracellular Polymeric Substance Matrix - genetics; Extracellular Polymeric Substance Matrix - metabolism; extracellular polymeric substances; Gene expression; Gene Expression Regulation, Bacterial; Genes; Genetic engineering; Immune system; Kinases; Lipids; Listeria; Listeria monocytogenes; Listeria monocytogenes - genetics; Listeria monocytogenes - physiology; Listeriosis; Metabolism; Metabolites; Mutation; Nutrient availability; Nutrients; Original; Pathogens; Penicillin; Peptides; Peptidoglycan - genetics; Peptidoglycan - metabolism; peptidoglycan synthesis; Polymerization; Proteins; Quorum sensing; Quorum Sensing - genetics; S-Adenosylmethionine - metabolism; Supplements; Transcription; Virulence; extracellular polymeric substances; quorum sensing; activated methyl cycle; biofilm; peptidoglycan synthesis
• ISSN: 2045-8827; 2045-8827
• DOI: 10.1002/mbo3.1015

Listeria monocytogenes is the causative agent of human listeriosis which has high hospitalization and mortality rates for individuals with weakened immune systems. The survival and dissemination of L. monocytogenes in adverse environments can be reinforced by the formation of biofilms. Therefore, this study aimed to understand the mechanisms underlying listerial biofilm development. Given that both nutrient availability and quorum sensing (QS) have been known as the factors influencing biofilm development, we hypothesized that the signal from a sentinel metabolite S‐adenosylmethionine (SAM) and Agr‐based QS could be synchronous in L. monocytogenes to modulate nutrient availability, the synthesis of extracellular polymeric substances (EPSs), and biofilm formation. We performed biofilm assays and quantitative real‐time PCR to investigate how biofilm volumes and the expression of genes for the synthesis of EPS were affected by SAM supplementation, agr deletion, or both. We found that exogenously applied SAM induced biofilm formation and that the expression of genes encoding the EPS synthesis machineries was regulated by SAM and/or Agr QS. Moreover, the gene transcription of components acting in the methyl cycle for SAM synthesis and Agr QS was affected by the signals from the other system. In summary, we reveal an interconnection at the transcriptional level between metabolism and QS in L. monocytogenes and highlight the critical role of metabolite‐oriented QS in biofilm development.
This study revealed mechanisms underlying EPS synthesis for biofilm development of Listeria monocytogenes. Especially, it elaborated on the cooperation of signal molecules in metabolic pathways and the quorum sensing (QS) network. These findings pave a way for systematically targeting key regulators in L. monocytogenes metabolism and QS to prevent biofilm development.