Author:
Li Huaxiang,Yang Xiao-jun,Zhu Xiao-yan,Gao Lu,Rao Sheng-qi,Yuan Lei,Yang Zhen-quan
Abstract
Cronobacter sakazakii (C. sakazakii) is an important pathogen contaminating dairy products (e.g., milk pow-der) and causes high mortality in infants. Bacteriophage as a potential biocontrol agent is a good alternative method for the control of this pathogen in dairy production and its environment. Thus, it is important to complete the C. sakazakii phage library by isolating and characterizing the broad host range of bacteriophage against C. sakazakii for control use. In this study, C. sakazakii strains from different sources were used as hosts to isolate and purify phages from human stool and sewage samples by double-layer plates. The biological characteristics, antibacterial properties, and genomes of these phages were then studied. Finally, ten virulent phages (EspYZU01–EspYZU10) infecting C. sakazakii were isolated and identified as belonging to the Myoviridae, Podoviridae, Tectivirus, and Stylovinidae families. Phage EspYZU08 presented the broadest host range and could infect all the five host strains of C. sakazakii. All 10 phages retained their infectivity at 50°C and pH 5–9. Both genomes of EspYZU05 and EspYZU08 were double-stranded DNAs with sizes of 41723 bp and 145582 bp, G+C contents of 55.69% and 46.75%, and open reading frames of 47 and 103, respectively. No toxins and antibiotic resistance genes were detected in both EspYZU05 and EspYZU08. Phage EspYZU08 and phage cocktail-3 (EspYZU01 + EspYZU03 + EspYZU08 + EspYZU09 + EspYZU10) presented excellent antibacterial efficacy for C. sakazakii in liquid broth and milk at 4°C, 25°C, and 37°C, suggesting that the phages in this study have great potential for the development of biocontrol agents against C. sakazakii in dairy and its processing environment.
Subject
Agronomy and Crop Science,Food Science
Cited by
13 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献