共培养沙门菌对粪肠球菌N41株生长特性及毒力基因的影响

发布时间：2019-03-03 10:26

【摘要】：为探讨共培养条件下沙门菌对粪肠球菌N41分离株生长特性及其不同生长时期26种毒力基因转录的影响,将N41菌株、沙门菌菌株单独/混合培养后,分别进行菌落计数并绘制生长曲线,观察其生长状况及影响,同时提取其对数中期、对数后期、稳定前期和稳定期的总RNA,SYBR GreenⅠ实时荧光定量PCR方法分析N41菌株26种毒力基因的转录情况。结果显示,共培养后沙门菌和N41生长均受到影响,其中,在N41菌体浓度降低约3.9倍,而沙门菌菌体浓度降低约110倍。在N41菌株26种毒力基因中,沙门菌促进了ebpA、ebpC、rnjB、ace、ebpR、psr等12种毒力基因在4个不同生长时期的转录,但同时也降低了毒力基因SlyA和sprE在4个生长期中转录水平;另外,除了CylL-S、CylL-L、efaA和AS在4个生长时期变化不明显外,其余的大部分毒力基因都在对数后期转录水平有明显上升,但在其他生长时期则表现不同。这说明,两菌共培养后,N41菌株明显抑制了沙门菌的生长,同时沙门菌也整体促进了N41菌株毒力基因的转录。本试验为研究细菌间相互作用机制以及肠球菌的致病机制奠定基础。
[Abstract]:In order to investigate the effects of Salmonella on the growth characteristics of Enterococcus faecalis N41 isolates and the transcription of 26 virulent genes at different growth stages under co-culture conditions, the strains N41 and Salmonella strains were isolated or co-cultured. Colony count was carried out and growth curve was drawn to observe the growth status and influence. At the same time, the total RNA, of logarithmic, Prophase and stable phase were extracted. The transcription of 26 virulent genes of N41 strain was analyzed by SYBR Green 鈪，

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