【作者】 熊慧生； 刘志林； 张鑫； 贾泽林； 崔佳宇； 张宇航； 马羽洁； 王学理；

【Author】 XIONG Huisheng;LIU Zhilin;ZHANG Xin;JIA Zelin;CUI Jiayu;ZHANG Yuhang;MA Yujie;WANG Xueli;College of Animal Science and Technology, Inner Mongolia Minzu University;

【机构】 内蒙古民族大学动物科技学院；

【摘要】 目的对蜡样芽孢杆菌的生物膜形成能力进行了鉴定,并探究了乳酸(lactic acid,LA)和过氧乙酸(peroxyaceticacid,PAA)对B. cereus生物膜的抑制机理。方法通过分析生物膜抑制生长曲线、生物膜代谢活性、胞外基质成分(多糖和蛋白质)含量、形态及相关基因表达,来评估LA和PAA对蜡样芽孢杆菌生物膜形成作用的影响。结果表明,蜡样芽孢杆菌可生成生物膜。LA和PAA对B. cereus的最小抑菌浓度(Minimum Inhibitory Concentrations,MIC)分别为0.252%(v/v)、0.030%(v/v)。生长曲线表明,1/2MIC、MIC LA、PAA可显著抑制B. cereus生物膜的形成。由Cell Counting Kit-8 (CCK-8)法检测生物膜代谢活性可知,MIC LA和PAA,使B. cereus生物膜的代谢活性分别降低了61.02%和69.27%。同时,由硫酸-苯酚法及考马斯亮蓝法对蜡样芽孢杆菌胞外多糖及胞外蛋白检测结果可知,MIC下LA、PAA处理组的胞外多糖分别降低了64.34%和79.14%,胞外蛋白质分别降低了78.96%和80.52%。通过结晶紫染色,对生物膜进行显微镜下观察,结果显示1/4 MIC下的LA、PAA即可抑制蜡样芽孢杆菌生物膜的生成。另外,通过实时定量聚合酶链反应确定,MIC下的LA、PAA显著抑制了蜡样芽孢杆菌生物膜相关基因(gapB、pgm、flgE、SigB、abrB、calY、sipW、tasA)的表达。结论研究结果表明,LA、PAA可以作为安全的抗生物膜剂来抑制蜡样芽孢杆菌的生物膜形成。更多还原

【Abstract】 Objective to characterize the biofilm-forming capability of B. cereus and elucidate the inhibitory mechanisms of lactic acid(LA) and peroxyacetic acid(PAA) on the biofilm formation. Methods the impact of lactic acid(LA) and peracetic acid(PAA) on the biofilm formation of Bacillus cereus was comprehensively evaluated by analyzing biofilm inhibition growth curves, biofilm metabolic activity, extracellular matrix components(including polysaccharides and proteins), morphological characteristics, and the expression levels of biofilm-related genes. The results showed that Bacillus cereus could form biofilms. The minimum inhibitory concentrations(MICs) for LA and PAA against B. cereus were 0.252%(v/v) and 0.030%(v/v), respectively. The biofilm growth curves indicated that LA and PAA at 1/2 MIC and MIC levels significantly curtailed the biofilm formation of B. cereus. The cell counting kit-8(CCK-8) assay demonstrated that LA and PAA at MIC levels reduced the biofilm metabolism activity of B.cereus by 61.02% and 69.27%, respectively. The sulfuric acid-phenol and Coomassie brilliant blue staining results revealed that MIC levels of LA and PAA diminished extracellular polysaccharides by 64.34% and 79.14% and extracellular proteins by 78.96% and 80.52%, respectively. Microscopic examination following crystal violet staining confirmed that even at 1/4 MIC levels, LA and PAA impeded the biofilm formation of B. cereus. Furthermore,real-time quantitative PCR indicated that the MIC levels of LA and PAA markedly downregulated the expression of biofilm-related genes(gapB, pgm, flgE, SigB, abrB, calY, sipW, and tasA) in B. cereus. The conclusion of the research shows that LA and PAA can be used as safe antibiofilm agents to inhibit the biofilm formation of Bacillus cereus.更多还原