Exploring the feasibility of Salmonella Typhimurium-specific phage as a novel bio-receptor

In Young Choi; Do Hyeon Park; Brayan A Chin; Cheonghoon Lee; Jinyoung Lee; Mi-Kyung Park

doi:10.5187/jast.2020.62.5.668

Exploring the feasibility of Salmonella Typhimurium-specific phage as a novel bio-receptor

J Anim Sci Technol. 2020 Sep;62(5):668-681. doi: 10.5187/jast.2020.62.5.668. Epub 2020 Sep 30.

Authors

In Young Choi¹, Do Hyeon Park¹, Brayan A Chin², Cheonghoon Lee³, Jinyoung Lee⁴, Mi-Kyung Park¹

Affiliations

¹ School of Food Science and Biotechnology, and Food and Bio-Industry Research Institute, Kyungpook National University, Daegu 41566, Korea.
² Materials Research and Education Center, Auburn University, Auburn, AL 36849, USA.
³ Graduate School of Public Health, and Institute of Health and Environment, Seoul National University, Seoul 08826, Korea.
⁴ Gyedong General Education Institute, Sangmyung University, Cheonan 31066, Korea.

Abstract

The purpose of this study was aimed to isolate a Salmonella Typhimurium-specific phage (KFS-ST) from washing water in a poultry processing facility and to investigate the feasibility of the KFS-ST as a novel bio-receptor for the magnetoelastic (ME) biosensor method. KFS-ST against S. Typhimurium was isolated, propagated, and purified using a CsCl-gradient ultracentrifugation. Morphological characteristics of KFS-ST were analyzed using transmission electron microscopy (TEM). Its specificity and efficiency of plating analysis were conducted against 39 foodborne pathogens. The temperature and pH stabilities of KFS-ST were investigated by the exposure of the phage to various temperatures (-70°C-70°C) and pHs (1-12) for 1 h. A one-step growth curve analysis was performed to determine the eclipse time, latent time and burst size of phage. The storage stability of KFS-ST was studied by exposing KFS-ST to various storage temperatures (-70°C, -20°C, 4°C, and 22°C) for 12 weeks. KFS-ST was isolated and purified with a high concentration of (11.47 ± 0.25) Log PFU/mL. It had an icosahedral head (56.91 ± 2.90 nm) and a non-contractile tail (225.49 ± 2.67 nm), which was classified into the family of Siphoviridae in the order of Caudovirales. KFS-ST exhibited an excellent specificity against only S. Typhimurium and S. Enteritidis, which are considered two of the most problematic Salmonella strains in the meat and poultry. However, KFS-ST did not exhibit any specificity against six other Salmonella and 27 non-Salmonella strains. KFS-ST was stable at temperature of 4°C to 50°C and at pH of 4 to 12. The eclipse time, latent time, and burst size of KFS-ST were determined to be 10 min, 25 min and 26 PFU/ infected cell, respectively. KFS-ST was relatively stable during the 12-week storage period at all tested temperatures. Therefore, this study demonstrated the feasibility of KFS-ST as a novel bio-receptor for the detection of S. Typhimurium and S. Enteritidis in meat and poultry products using the ME biosensor method.

Keywords: Bio-receptor; Magnetoelastic biosensor; Meat and poultry; Salmonella-specific phage.