摘要
该研究以食源性致病菌单增李斯特菌为研究对象,考察了培养时间、培养温度、pH值及NaCl浓度等不同环境因素对单增李斯特菌产群体感应信号分子Autoinducer-2(AI-2)活性与生物被膜形成的影响。结果表明:在对数生长期,单增李斯特菌AI-2活性随着菌密度增加而增加,到达稳定期后AI-2活性呈下降的趋势;在聚苯乙烯培养板中于37℃培养24 h,单增李斯特菌的生长量、生物被膜产生量及AI-2活性最高,分别是4℃下的7.65倍、11.14倍和4.40倍;在质量分数为0.5%~9.0%的NaCl添加量下,单增李斯特菌的生长量相近,NaCl质量分数为3.0%时,AI-2活性最高,相对荧光强度为6.159,而NaCl质量分数为9.0%时,生物被膜形成量与AI-2活性最低;pH值为5和9时的AI-2活性分别为对照组(pH值7.4)的0.11倍和0.13倍,均受到显著的抑制。以上结果说明单增李斯特菌的AI-2活性与生物被膜形成受环境因素的影响,为进一步研究LuxS/AI-2群体感应系统调控生物被膜形成及其淬灭提供参考。
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.
作者
黄铭新
张杏果
叶国良
李婷
吴金松
钟青萍
HUANG Mingxin;ZHANG Xingguo;YE Guoliang;LI Ting;WU Jinsong;ZHONG Qingping(Guangdong Provincial Key Laboratory of Food Quality and Safety,College of Food Science,South China Agricultural University,Guangzhou 510642,China)
出处
《现代食品科技》
北大核心
2025年第1期74-80,共7页
Modern Food Science and Technology
基金
广东省基础与应用基础研究基金项目(2024A1515012695
2021A1515011083)
国家自然科学基金面上项目(31972046)
广东省科技计划项目(2020B1212060059)。
