Comparison of AI-2 Signaling Molecule Production and Biofilm Formation by Listeria monocytogenes under Different Environmental Conditions
HUANG Mingxin
ZHANG Xingguo
YE Guoliang
LI Ting
WU Jinsong
ZHONG Qingping
Abstract：We investigated the effects of different environmental factors,namely,culture time and temperature,pH,and NaCl concentration,on autoinducer(AI-2)activity and biofilm formation of the foodborne pathogen Listeria monocytogenes.The results revealed that during the logarithmic growth period,the AI-2 activity of L.monocytogenes was initially enhanced with an increase in cell density,although on reaching the stable growth period,the activity showed a subsequent declining trend.The highest values for growth,biofilm biomass,and AI-2 activity were recorded when L.monocytogenes was cultured in polystyrene culture plates at 37℃for 24 h,which were 7.65-,11.14-,and 4.40-fold higher than the values obtained at 4℃,respectively.Listeria monocytogenes showed similar growth performance in response to the addition of 0.5-9.0 wt.%NaCl,with AI-2 activity peaking at a NaCl mass fraction of 3.0%and a relative fluorescence intensity of 6.159.The lowest values of biofilm biomass and AI-2 activity were recorded at an NaCl mass fraction of 9.0%.Moreover,at pH value 5 and pH value 9,AI-2 activities were 0.11-and 0.13-fold compared to the control group(pH value 7.4),respectively,indicating a significant inhibition of activity at both low and high pH values.Collectively,these findings indicate that AI-2 activity and biofilm formation of L.monocytogenes are influenced by environmental factors.These findings will provide a reference for further research on the regulation of biofilm formation by the LuxS/AI-2 quorum sensing system and its quenching.
Keywords：Listeria monocytogenesbiofilmenvironmental factorAI-2 signaling molecule
Publication Date：2025-01-14
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 74-80 )