PlcR在炭疽芽胞杆菌A16R中的功能研究

The function of PlcR in Bacillus anthracis vaccine strain A16R

炭疽芽胞杆菌(Bacillus anthracis)、蜡样芽胞杆菌(B.cereus)和苏云金芽胞杆菌(B.thuringiensis)均属于蜡样芽胞杆菌群,在遗传学上有很高的相似性。PlcR(Phospholipase C regulator)在蜡样芽胞杆菌中是十分重要的调控因子,但plc R基因在炭疽芽胞杆菌中发生一个无义突变导致在炭疽芽胞杆菌中产生一个截短Plc R蛋白。为了研究plc R基因对炭疽芽胞杆菌功能的影响,文章以蜡样芽胞杆菌CMCC6330基因组为模板,构建重组表达质粒p BE2A-plc R后导入炭疽芽胞杆菌疫苗株A16R中获得重组菌株,对其进行表型分析。结果显示,炭疽芽胞杆菌重组菌株的溶血活性基本没有恢复,但恢复了部分神经鞘磷脂酶活性,表明将蜡样芽胞杆菌的plc R基因导入炭疽芽胞杆菌后,可以直接激活神经鞘磷脂酶活性。

Bacillus anthraeis, B. thuringiensis and B. cereus are members of the B. cereus group. They share high genetic similarity. Whereas plcR （Phospholipase C reguIator） usually encodes a functional pleiotropic activator pro- tein in B. cereus and B. thuringiensis isolates, a characteristic nonsense mutation is found in all B. anthracis strains investigated, making the gene dysfunctional. To study the function of PlcR in B. anthracis, we used the B. cereus CMCC63301 genome as a template and constructed a recombinant expression plasmid pBE2A-plcR, and introduced it into the B. anthracis vaccine strain A16R, and then analyzed the activity of the hemolysin and sphingomyelinase. The results showed that transformation of B. anthracis with plasmid pBE2A-plcR carrying the native B. cereus plcR gene active the expression of sphingomyelinase gene, but did not activate expression of hemolysin genes of B. anthracis A16R.