培养条件对副溶血性弧菌AI-2活性及其合成关键基因表达水平的影响

Effects of different culture conditions on AI-2 activities and expression levels of the critical genes involved in AI-2 synthesis in Vibrio parahaemolyticus

中文关键词:  副溶血性弧菌  信号分子AI-2  luxS  pfs

英文关键词:Vibrio parahaemolyticus  signal molecules autoinducer-2 (AI-2)  luxS  pfs

中文摘要:

      目的 以海产品中分离的一株高产信号分子AI-2(Autoinducer-2)的副溶血性弧菌Vp2009027为研究对象, 分析不同的培养条件(时间、温度、糖源、pH和盐度)对菌株AI-2活性及其合成关键基因表达水平的影响。方法 采用报告菌株检测AI-2的活性变化, 采用逆转录-实时荧光定量PCR法检测合成关键基因luxS和pfs表达量的变化。结果 菌株培养12 h后AI-2活性达到最高, 当培养温度为30℃时AI-2活性最高, 添加糖源、中性和偏碱性环境以及适度的盐度均可促进AI-2活性的提高; 不同培养条件下AI-2合成关键基因luxS和pfs的表达量均有不同程度的变化, 温度和糖源对AI-2活性的影响与对luxS和pfs基因表达量的影响呈正相关, 其他条件下AI-2的活性与luxS和pfs的表达量没有明显相关性。结论 不同培养条件可以调控AI-2的合成, 可以通过改变培养条件来获得不同产量的AI-2。

英文摘要:

      Objective Taking Vibrio parahaemolyticus Vp2009027, a strain with high-intensity signal molecule autoinducer-2 (AI-2) isolated from seafood as the research object, to study the effects of culture conditions (time, temperature, sugar source, pH and salinity) on the activity of AI-2 and the expression level of the critical genes involved in synthesis of AI-2. Methods The activity of AI-2 was assayed using the reporter strain and the expression level of the critical genes luxS and pfs was determined by reverse transcription-realtime quantitative PCR. Results The AI-2 activity reached the highest after 12 h cultivation, and the AI-2 activity was the highest when the cultivation temperature was 30 ℃. Sugar supplemented in media, the neutral and alkaline condition, and moderate salinity could increase the activity of AI-2. Under different culture conditions, the expression levels of the key genes of AI-2 synthesis, luxS and pfs, had varying degrees of change. The influence of temperature and glycogen on the activity of AI-2 was positively correlated with the effect on the expression of luxS and pfs genes. Under other conditions, the activity of AI-2 had no significant correlation with the expression of luxS and pfs Conclusion Different culture conditions can regulate the synthesis of AI-2, and different production of AI-2 can be obtained by changing the culture conditions.