PFOS对哈维氏弧菌生长及外毒素基因的影响

Impact of PFOS on Growth and ECP Gene of Vibrio harveyi

探讨了全氟辛烷磺酸盐(PFOS)对哈维氏弧菌密度及外毒素基因表达的影响。用含有不同浓度PFOS(5、50、500 mmol/L)的培养基培养哈维氏弧菌,分别在6、15、24 h取适量菌液,经4 000 r/min离心,磷酸盐缓冲液(PBS)洗涤3次,制成PBS菌悬液。采用实时荧光定量PCR检测其胞外蛋白酶、溶血素及保守序列16 SrRNA基因在不同培养时间的拷贝数。结果表明,仅5mmol/L PFOS对细菌生长有明显的抑制作用(P<0.01),其它两浓度均无明显影响。3个浓度的PFOS都使胞外蛋白酶和溶血素基因的拷贝数有明显增加(P<0.01),而16 SrRNA的基因拷贝数仅受低浓度的5 mmol/L PFOS影响而有所增加(P<0.01)。同时,溶血素基因与16 SrRNA类似,对低浓度PFOS更为易感。提示PFOS对哈维氏弧菌的生长及基因有一定影响,尤以低浓度PFOS为甚。

The effect of perfluorooctane sulphonate（PFOS） on the Vibrio harveyi cell density and expression of extra-toxin gene was investigated.The Vibrio harveyi samples,which cultured in LB media with different PFOS concentrations（5,50,500 mmol/L）,were collected by centrifugation（4 000 r/min） after 6,15 and 24 h incubation,respectively,and cell sediments were re-suspend in phosphate buffer solution（PBS）.And the RT-PCR was used for analyzing the gene expression of extracellular protease,hemolysin and 16 SrRNA conserved sequence.The results shown that the cell density was inhibited significantly in the medium with 5 mmol/L PFOS（P0.01）,but not for 50 mmol/L and 500 mmol/L.While three different concentration of PFOS enhanced the expression gene of ECP and hemolysin（P0.01）.However,the gene expression of 16 SrRNA conserved sequence was boosted by 50 mmol/L PFOS only（P0.01）.The hemolysin was also sensitive to the lower PFOS concentration.In sum,the data in this paper indicated the lower PFOS concentration will impact on the growth and gene expression of Vibrio harveyi.