福氏志贺菌mdoC基因对其在洗菜水中生长及生物膜形成的影响  

Study on the effects of gene mdoC of Shigella flexneri on the growth of bacteria and biofilm formation in vegetable wash waters

作　　者：刘柳[1,2] 樊明涛[1] Bhagwat A Arvind 

机构地区：[1]西北农林科技大学食品科学与工程学院,陕西杨凌712100 [2]U S Department of Agriculture Agricultural Research Service Environmental Microbial and Food Safety Laboratory,Beltsville,MD20705,USA

出　　处：《西北农林科技大学学报（自然科学版）》2009年第12期175-180,共6页Journal of Northwest A&F University(Natural Science Edition)

基　　金：陕西省科技攻关项目(2008K01-06)

摘　　要：【目的】研究福氏志贺菌mdoC基因对细菌在不同洗菜水中生长及生物膜形成的影响。【方法】以福氏志贺菌野生型和敲除mdoC基因的opgC突变体为出发菌株,采用生长曲线法和结晶紫染色法,在低渗透压及正常渗透压的菠菜、芹菜、生菜及白菜洗菜水中,研究福氏志贺菌野生型和opgC突变体生长及生物膜的产生能力。【结果】在不同洗菜水中,福氏志贺菌opgC突变体生长速率明显较野生型慢,加盐提高渗透压之后,野生型和opgC突变体稳定生长期均提前。野生型和opgC突变体的生物膜产量在菠菜水、生菜水和白菜水中有显著区别;提高渗透压之后,福氏志贺菌野生型在菠菜水中的生物膜产量显著提高,而在生菜水和白菜水中生物膜产量显著下降,opgC突变体在菠菜水、生菜水和白菜水中生物膜产量均显著提高。【结论】低渗条件下,福氏志贺菌mdoC基因的缺失显著地延缓了细菌生长。提高渗透压后,在菠菜、生菜和白菜洗菜水中,mdoC基因的缺失促进了生物膜的形成。[Objective] This study was to explore the effect of gene mdoC of Shigella fle：rneri on the growth of bacteria and biofilm formation in the different vegetable wash water. [Method] The growth curves of Shigella flexneri and mdoC gene knock out opgC mutant were measured and the biofilm was quantified by crystal violet assay to study the growth of bacteria and biofilm formation under hypoosmotic and normal conditions in spinach, green celery, lettuce and cabbage wash water. [Result] The results showed that the growth rate of opgC mutant was lower than wild type in different wash water, while the wild type and opgC mutant grew faster under normal osmolarity than hypoosmotic wash water;there were significant differences between the biofilm formation of wild type and that of opgC mutant in spinach,lettuce and cabbage wash water. After increasing the osmolarity of wash water,the quantity of biofilm formed by wild type in spinach wash water increased significantly, while the biofilm in lettuce and cabbage wash water decreased. There were significant increases for the biofilm formation of opgC mutant in spinach,lettuce and cabbage wash water when the osmolarities were adjusted up to the normal ones. [Conclusion] The gene mdoC deletion in Shigella flexneri retarded significantly the growth at hypoosmotic condition,while the deletion increased the biofilm formation in cabbage wash water after increasing the osmolarity to norreal level.

关 键 词：福氏志贺菌 opgC突变体 渗透调节周质葡聚糖 生物膜 洗菜水 

分 类 号：X503.231[环境科学与工程—环境工程]