产气荚膜梭菌噬菌体鉴定及其环境消减效果评价

分离获得1株禽源产气荚膜梭菌(Clostridium perfringens,Cp)噬菌体，拟鉴定其生物学特性及裂解力，并在环境中应用评价其对Cp的消减效果。通过双层及单层平板法从肉鸡肠道组织样品中分离并纯化1株Cp噬菌体。运用透射电镜观察该噬菌体形态，分析其MOI、一步生长曲线、pH及温度耐受特性、宿主谱及体外抗菌活性。通过基因组测序分析其基因组信息，最终在模拟环境下评价噬菌体对Cp污染量消减效果。扫描电镜结果显示，该噬菌体为长尾噬菌体，潜伏期<20 min,爆发量为28.5 PFU·cell^-1,最佳MOI为0.01,能够特异性裂解禽源Cp菌株，对待检的43株Cp裂解率高达83.72%。基因组分析表明，该噬菌体为双链DNA噬菌体，全长41 590 bp,拥有59个开放阅读框，其中33个ORF与已知功能蛋白具有一定同源性，将该噬菌体命名为vB＿CpeS＿SD72。小亚基末端酶构建进化树分析表明，噬菌体与Clostridium phage vB CpeS-CP51同源性较高。在环境消减测试中观察到噬菌体作用0.5 h,杀菌效率可达98.36%;2 h能够抑制...

Identification and Environmental Inhibition Effect of Clostridium perfringens Phage

This study attempted to isolate a novel C. perfringens (Cp) phage from poultry. Biological characteristics and genomic information have been analyzed, which can provide new strategy for Cp infection and control. A Cp phage was isolated and purified from broiler intestinal tissue samples by double-layer and single-layer plate methods. The morphology of the phage was observed by transmission electron microscope, and the MOI, one-step growth curve, pH and temperature tolerance characteristics, host range and antibacterial activity in vitro were analyzed. The genomic information was analyzed by genome sequencing, and finally the effect of phage on reducing the pollution of Cp was evaluated in a space simulated environment. The results showed that the electron microscope showed that the phage was a long tailed phage, the latent period was less than 20 min, the burst size was 28.5 PFU·cell^-1, and the best MOI was 0.01. It could specifically inhibit avian Cp strains, and the host range was as high as 83.72%. Genome analysis showed that the phage was a double stranded DNA phage with a total length of 41 590 bp and 59 open reading frames (ORF), of which 33 ORFs had certain homology with known functional proteins. The phage was named as vB_CpeS_SD72. The phylogenetic tree analysis of terminase small subunit showed that the phage had high homology with Clostridium phage vB CpeS-CP51. In the environmental control test, it was observed that the phage could inhibit 98.36% Cp at 30 min and nearly completely inhibited within 2 h. A novel Cp phage with strong lytic activity can effectively inhibit Cp contamination in the environment, which provide a powerful strategy candidate source for Cp pollution and control in food, animal breeding and livestock and poultry products.