檀香醇对猪多杀性巴氏杆菌DCS株的抑菌效果及作用机制的研究

Antibacterial effect and mechanisms of santalol to Pasteurella multocida DCS strain

为了探讨檀香醇对多杀性巴氏杆菌(Pm)的抑菌效果,以Pm DCS分离株为研究对象,采用倍比稀释法测定了檀香醇对Pm DCS株的最小抑菌浓度(MIC50),利用小鼠检测檀香醇的体内抑菌效果。同时分别利用实时荧光定量PCR(qPCR)及聚丙烯酰胺凝胶电泳(SDS-PAGE)检测檀香醇对Pm DCS株细胞分裂相关基因和核糖体基因的表达及细菌蛋白表达的影响。结果显示,Pm DCS株对小鼠的LD50为1×105CFU/m L,檀香醇对Pm DCS株的MIC50为128μg/m L。每只经256和512μg檀香醇处理24 h的Pm DCS株感染小鼠,肺部细菌计数明显低于生理盐水组小鼠。细菌经64、128、256μg/m L檀香醇处理24 h后,菌体蛋白的表达量降低。qPCR检测结果显示,Pm DCS株经檀香醇处理后,体内ftsZ、ftsW、zipA和slmA基因的表达量极显著降低(P<0.01),rpoE、rpmJ、rpsJ、rpsI和rpsA基因的表达量显著降低(P<0.05),rpsC和rpsO基因的表达量显著升高(P<0.05)。可见,檀香醇可通过降低细菌的细胞分裂相关基因的表达量而干扰细菌细胞的分裂,同时通过扰乱核糖体基因对细胞某些蛋白的表达,从而产生抑菌作用。

In order to investigate the antibacterial effect of santalol on Pasteurella multocida(Pm),the minimum inhibitory concentration(MIC50) of santalol on Pm DCS strain was determined by double dilution method and the in vivo antibacterial effect of santalol on Pm DCS was studied in mice.Real-time quantitative PCR(q PCR) were used to explore the inhibitory effects of santalol on the expression of cell division-related genes and ribosomal genes.And SDS-PAGE was used to detect protein expression of Pm DCS.The results showed that the LD50of P.multocida DCS strain in mice was 1×105CFU/m L and MIC50of santalol to Pm DCS was 128 μg/m L.Bacterial counts in lungs of mice treated with 256 μg and 512 μg per mouse were less than that in lungs of control mice.After treatment with 64,128,256 μg/m L santalol for 24 h,the protein expression of Pm DCS decreased.q PCR detection results showed that cell division-related genes fts Z,fts W,zip A and slm A expression of santalol-treated Pm DCS were very significantly decreased(P<0.01).And ribosomal genes,rpo E,rpm J,rps J,rps I and rps A expression were significantly decreased(P<0.05),but ribosomal genes,rps C and rps O were significantly increased(P<0.05).In conclusion,santalol could inhibit the growth and multiply of Pm DCS to a certain extent by regulating the expression of some cell division-related and ribosomal genes and inhibiting the expression of some proteins in Pm DCS.