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ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Produce Safety and Microbiology Research » Research » Publications at this Location » Publication #412233
Research Project: Elucidating the Factors that Determine the Ecology of Human Pathogens in Foods

Location: Produce Safety and Microbiology Research

Title: A new member of Tequintavirus bacteriophage isolated from sewage water with antimicrobial potential against multidrug-resistant Salmonella Infantis strains

Author
item Liao, Yen-Te
item VOELKER, ANGELA - Hispanic Association Of Colleges & Universities (HACU)
item Zhang, Yujie
item HO, KAN-JU - Forest Service (FS)
item Salvador, Alexandra
item Wu, Vivian

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 2/28/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Recently, Salmonella Infantis has increased considerably and is of great concern in the poultry industry. Due to antibiotic resistance, alternative approaches, such as phage application, are necessary to control S. Infantis. Although various phages have been isolated to control Salmonella enterica, the lytic phages targeting Salmonella Infantis are relatively scarce. Thus, the objective was to characterize a new Demerecviridae phage from sewage water for the antimicrobial potential against multidrug-resistant Salmonella Infantis. Salmonella phages vB_SalS-SIA3lw (or SIA3lw) was isolated from sewage water using S. Infantis ATCC BAA-1675. Purification via CsCl gradient was conducted before DNA extraction, whole-genome sequencing analysis, and transmission electron microscopy observation. Phage stability tests, one-step growth curve, and antimicrobial activity tests, such as host range and in vitro bacterial challenge test with different phage concentrations (MOI=1, 10, and 100), were also conducted. Phage SIA3lw has Siphoviridae morphology and genomically belongs to the genus Tequintavirus under the family Demerecviridae (Table 1). The phylogenic analysis shows that SIA3 does not share an evolutionary relationship with any close-related reference phages belonging to the genus Tequintavirus. Phage SIA3lw has a latent period of 30 min with a burst size of 150 PFU/CFU against S. Infantis ATCC BAA-1675. The phage shows lytic infection against 13 out of 14 additional S. Infantis strains of different sources and generic E. coli strains (ATCC13706 and ATCC15597), mostly with medium- to high-producing efficiency. Among different concentrations, MOI=100 was the most effective in reducing both multidrug-resistant and multidrug-sensitive S. Infantis strains to the lowest levels in vitro after a single treatment for 2 h at 25'C, with 0.8 and 0.6 log reduction, respectively, compared to the control. Additionally, the 2nd phage treatment with MOI=100 applied 2 h after the 1st dose resulted in more bacterial reduction than the single treatment at the 4-h timepoint. The findings provide insight into a new member of the Demerecviridae phage as an alternative antimicrobial agent for controlling multidrug-resistant Salmonella Infantis strains.