Yang Meiyan, Liang Yongjian, Huang Shixuan, Zhang Jumei, Wang Jing, Chen Hanfang, Ye Yuanming, Gao Xiangyang, Wu Qingping, Tan Zhiyuan
College of Agriculture, South China Agricultural University, Guangzhou, China.
State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbiology Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, Guangzhou, China.
Front Microbiol. 2020 Feb 21;11:259. doi: 10.3389/fmicb.2020.00259. eCollection 2020.
Accumulating evidence has indicated that the multiple drug resistant may pose a serious threat to public health and economic concerns for humans globally. Here, two lytic bacteriophages, namely vB_VpS_BA3 and vB_VpS_CA8, were isolated from sewage collected in Guangzhou, China. Electron microscopy studies revealed both virions taxonomically belonged to the family with icosahedral head and a long non-contractile tail. The double-stranded DNA genome of phage BA3 was composed of 58648 bp with a GC content of 46.30% while phage CA8 was 58480 bp with an average GC content of 46.42%. In total, 85 putative open reading frames (ORFs) were predicted in the phage BA3 genome while 84 were predicted in that of CA8. The ORFs were associated with phage structure, packing, host lysis, DNA metabolism, and additional functions. Furthermore, average nucleotide identity analysis, comparative genomic features and phylogenetic analysis revealed that BA3 and CA8 represented different isolates but novel members of the family, . Regarding the host range of the 61 isolates, BA3 and CA8 had an infectivity of 8.2 and 36.1%, respectively. Furthermore, ∼100 plaque-forming units (pfu)/cell for phage BA3 and ∼180 pfu/cell for phage CA8 were determined to be the viral load under laboratory growth conditions. Accordingly, the phage-killing assay revealed that phage CA8 achieved approximately 3.65 log unit reductions. The present results indicate that CA8 is potentially applicable for biological control of multidrug resistant .
越来越多的证据表明，多重耐药菌可能对全球人类的公共卫生和经济问题构成严重威胁。在此，从中国广州收集的污水中分离出两种裂解性噬菌体，即vB_VpS_BA3和vB_VpS_CA8。电子显微镜研究表明，这两种病毒粒子在分类学上均属于具有二十面体头部和长非收缩性尾部的噬菌体家族。噬菌体BA3的双链DNA基因组由58648 bp组成，GC含量为46.30%，而噬菌体CA8为58480 bp，平均GC含量为46.42%。噬菌体BA3基因组中共预测出85个推定的开放阅读框（ORF），而CA8基因组中预测出84个。这些ORF与噬菌体结构、包装、宿主裂解、DNA代谢及其他功能相关。此外，平均核苷酸同一性分析、比较基因组特征和系统发育分析表明，BA3和CA8代表不同的分离株，但属于噬菌体家族的新成员。关于61株分离菌的宿主范围，BA3和CA8的感染性分别为8.2%和36.1%。此外，在实验室生长条件下，噬菌体BA3的病毒载量约为100噬菌斑形成单位（pfu）/细胞，噬菌体CA8约为180 pfu/细胞。因此，噬菌体杀灭试验表明噬菌体CA8实现了约3.65个对数单位的减少。目前的结果表明，CA8可能适用于多重耐药菌的生物防治。
