霍乱弧菌分型噬菌体VP2部分生物学特性及基因组分析

Partial biological characteristics and genomic analysis of Vibrio cholerae typing phage VP2

目的对霍乱弧菌分型噬菌体VP2基因组、蛋白质组和增殖特征等开展分析,获取VP2的生物学特征。方法电镜观察噬菌体VP2的形态,测定最佳感染复数和一步生长曲线;通过在线RAST(https://rast.nmpdr.org/)对噬菌体VP2基因组进行编码基因预测及功能注释;提取VP2成熟颗粒中的蛋白质进行质谱分析;使用pyani进行噬菌体全基因组平均核苷酸一致性(ANI)聚类分析。结果噬菌体VP2为典型的20面体短尾噬菌体,最佳感染复数为1∶100,一步生长曲线结果显示其潜伏期大约为60 min,60~120 min为暴发期,120 min后为稳定期。预测存在49个开放阅读框(ORF),VP2成熟颗粒蛋白质谱分析显示有34个蛋白与预测的基因相对应,ANI结果显示,VP2与弧菌噬菌体CJY的ANI最高。结论明确了分型噬菌体VP2的基本生物学和基因组特征,获得成熟颗粒中包含的蛋白成分,为后续研究同源噬菌体及其与霍乱弧菌的相互作用提供了基础。

Objective To further understand the biological characteristics of Vibrio cholerae typing phage VP2 by analyzing its whole genome proteome and proliferation.Methods The morphology of phage VP2 was observed under electron microscope,and the optimal multiplicity of infection(MOI)and one step growth curve were determined.Online RAST(https://rast.nmpdr.org/)was used to predict and annotate the encoding genes of the phage VP2 genome,and the proteins in the mature VP2 particles were analyzed by mass spectrometry.Phage genome average nucleotide consistency was analysis by using pyani.Results Phage VP2 was a typical 20-hedron short-tailed phage,the optimal MOI was 0.01.One step growth curve showed that incubation period of about 60 minutes,outbreak period of 60–120 minutes was,and the stable period was after 120 minutes.Forty-nine open reading frames(ORFs)were predicted.Protein spectrum analysis of mature VP2 particles showed that 34 proteins corresponded to the predicted genes.Ani cluster analysis showed that Ani was the highest in VP2 and Vibro phage CJY.Conclusion The biological and genomic characteristics of typing phage VP2 were identified and the protein of mature particles was obtained in this study,providing basic data for the further study of homologous phages and its interaction with V.cholerae.