致病性副溶血弧菌生物膜形成特性研究

Characteristics of biofilm formation of pathogenic Vibrio parahaemolyticus

采用改良的微孔板法测定了12株弧菌的形成生物膜的效果,选择形成生物膜效果最好的副溶血弧菌ND-02,进一步研究了环境因子对其生物膜形成的影响。实验结果显示副溶血弧菌ND-02菌株在静置培养24～36 h后形成成熟的生物膜,在起始菌浓度为107～108CFU/mL形成生物膜的量最大;在30℃,NaCl浓度为3%～5%,pH偏弱碱性时的生物膜OD590值最大;C 2a+促进副溶血弧菌生物膜的形成,而M 2g+抑制生物膜的形成;副溶血弧菌在分别经大黄鱼表皮黏液、肠黏液和肝脏提取液包被的的基质上形成生物膜的作用明显,鳃黏液和脾脏提取液中次之,肌肉提取液包被后生物膜形成量最低。以上结果表明,副溶血弧菌ND-02菌株能形成稳定而明显的生物膜,而且生物膜的形成受温度、NaCl浓度、pH值等环境因子的影响。

Biofilm formation of 12 strains of Vibrio were determinated using the method of modified microtiter-plate test,and V.parahaemolyticus strain ND-02 was chosen for the further study on the influence of different environmental factors on bacterial biofilm formation.The results show that V.parahaemolyticus strain ND-02 forms mature biofilm in 24～36 h,V.parahaemolyticus with original bacterial concentrations of 107 and 108CFU/mL shows the largest biofilm quantity;the OD590 value of bacterial biofilm increases with the incubation temperature from 10 ℃ to 30 ℃ and peaks at 30 ℃;the OD590 value of bacterial biofilm fluctuates with different NaCl concentrations optimized at 3% to 5%,and OD590 values are remarkably higher at pH 7～10,and peak at pH 7.Addition of C a2＋ obviously promoted the bacterial biofilm formation while M g2＋ played as an opposite role.V.parahaemolyticus strain ND-02 showed better biofilm formation on the wells coated with liver extract,skin mucus and intestinal mucus of Pseudosciaena crocea,the less biofilm was found on the wells coated with muscle extract.The results indicate that V.parahaemolyticus strain ND-02 develops stable and evident biofilm,the biofilm formation is remarkably affected by environmental factors,such as temperature,pH,NaCl concentration,C a2＋,M g2＋.The results also indicate that the bacterial biofilm formation of V.parahaemolyticus is governable,which will be useful for the epidemic control in fish culture.