Propagation method for persistent high yield of diverse Listeria phages on permissive hosts at refrigeration temperatures.
The efficient production of a high concentration of bacteriophage in large volumes has been a limiting factor in the exploration of the true potential of these organisms for biotechnology, agriculture and medicine. Traditional methods focus on generating small volumes of highly concentrated samples as the end product of extensive mechanical and osmotic processing. To function at an industrial scale mandates extensive investment in infrastructure and input materials not feasible for many smaller facilities. To address this, we developed a novel, scalable, generic method for producing significantly higher titer psychrophilic phage (P < 2.0 × 10(-6)), 2- to 4-fold faster than traditional methods. We generate renewable high yields from single source cultures by propagating phage under refrigeration conditions in which Listeria, Yersinia and their phages grow in equilibrium. Diverse Yersinia and Listeria phages tested yielded averages of 3.49 × 10(8) to 3.36 × 10(12) PFU/ml/day compared to averages of 1.28 × 10(5) to 1.30 × 10(10) PFU/ml/day by traditional methods. Host growth and death kinetics made this method ineffective for extended propagation of mesophilic phages.
Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario, N1G 5C9, Canada.
Devon R
DR
Radford
Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario, N1G 5C9, Canada; Department of Food Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada.
Hanie
H
Ahmadi
Agriculture and Food Laboratory, Laboratory Services Division, University of Guelph, Guelph, Ontario, N1H 8J7, Canada.
Carlos G
CG
Leon-Velarde
Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario, N1G 5C9, Canada. Electronic address: balamurugans@agr.gc.ca.
Sampathkumar
S
Balamurugan
D001435:Bacteriophages / Q000254:growth & development*; D003080:Cold Temperature; D008087:Listeria / Q000821:virology*; D019562:Viral Load; D010948:Viral Plaque Assay; D014776:Virus Cultivation / Q000379:methods*; D015007:Yersinia / Q000821:virology
Bacteriophage; Biotechnology; Food safety; Listeria monocytogenes; Phage replication; Yersinia enterocolitica