不同培养条件下sigB对单增李斯特菌生物被膜形成的影响  

Effects of sigB on biofilm formation by Listeria monocytogenes under various culture conditions

作　　者：付娇娇[1] 王旭[1] 刘海泉[1] 孙晓红[1,2,3] 谢晶[1,2,3] 潘迎捷[1,2,3] 赵勇[1,2,3] 

机构地区：[1]上海海洋大学食品学院,上海201306 [2]上海水产品加工及贮藏工程技术研究中心,上海201306 [3]农业部水产品贮藏保鲜质量安全风险评估实验室,上海201306

出　　处：《上海海洋大学学报》2016年第4期634-640,共7页Journal of Shanghai Ocean University

基　　金：国家自然科学基金面上项目(31271870;31571917);国家科技支撑计划(2015BAD17B01);上海市科委计划项目(14DZ1205100;14320502100);上海市科技兴农重点攻关项目(沪农科攻字2014第3-5号;2015第4-8号);上海水产品加工及贮藏工程技术研究中心(11DZ2280300)

摘　　要：本研究比较分析了不同温度(4、15、25和37℃)、pH(4、5、6和7)及NaCl浓度(0.5%、2.5%、4.5%和6.5%)对单增李斯特菌野生型菌株(WaX12)及sigB缺失突变型菌株(WaX12-ΔsigB)生物被膜形成能力的影响。结果表明,相比于WaX12菌株,WaX12-ΔsigB菌株生物被膜的形成量显著降低(P<0.05)。变异系数分析显示,不同培养条件对WaX12菌株及WaX12-ΔsigB菌株生物被膜形成能力均有影响,其中温度的影响最大,NaCl浓度次之,pH最弱;且WaX12-ΔsigB菌株生物被膜形成能力更易受到培养条件的影响。其次,分别选取了WaX12菌株与WaX12-ΔsigB菌株生物被膜形成量差异最显著的培养条件(37℃、pH6及2.5%NaCl)进行后续分析。结果发现WaX12-ΔsigB菌株胞外多糖及胞外蛋白的相对含量均显著降低(P<0.05),而其活菌数略有降低。本研究为深入探讨sigB参与单增李斯特菌生物被膜形成的分子机制提供科学依据。The role of sigB, a major transcriptional regulator of stress response genes of Listeria monocytogenes,was assessed in biofilm formation of wild type strain（ WaX12） and sig B deletion mutant（ Wa X12-ΔsigB） as affected by temperatures（ 4 ℃,15 ℃,25 ℃ and 37 ℃）,pH values（ 4,5,6 and 7）and NaCl concentrations（ 0. 5 %,2. 5 %,4. 5 % and 6. 5 %）. Results showed that the biofilm biomass was significantly reduced in L. monocytogenes mutant lacking sigB（ P〈0. 05）. According to the coefficient of variation analysis,all three of the culture conditions tested（ i. e.,temperature,pH and NaCl concentration）appeared to affect the strain variability of the biofilm formation of Wa X12 and Wa X12-ΔsigB,and the increase in the strain variability of biofilm formation caused by temperature is much greater than that caused by NaCl or pH. The ability of forming biofilm by WaX12-ΔsigB was more vulnerable to the effects of external culture conditions. There was a significant difference of biofilm biomass between WaX12 and Wa X12-ΔsigB at 37 ℃,pH 6 and 2. 5 % NaCl,respectively,so the further research was observed under these culture conditions.Notably,results showed that the relative amounts of total polysaccharides and extracellular proteins were much lower in WaX12-ΔsigB biofilm（ P〈0. 05）. However,there was little influence on live cells. In conclusion,this study could provide a scientific basis for further investigation of the important role of sigB in L.monocytogenes biofilm formation.

关 键 词：单增李斯特菌 生物被膜 SIGB 

分 类 号：TS201.3[轻工技术与工程—食品科学]