Ba plates

Campylobacter jejuni was routinely grown on blood agar base No.2 plates (BA plates; Oxoid) supplemented with 5% horse blood (TCS Biosciences) under microaerobic conditions in either a modular atmosphere controlled cabinet (5% CO₂, 5% O₂, 2% H₂, 88% N₂) or in anaerobic jars using gas replacement (7.3% CO₂, 5.6% O₂, 3.6% H₂, 83.5% N₂) at 42 °C. Bacteriophage DA10 was isolated as described previously [26 ] and propagated by plate lysis of the host C. jejuni GM. C. jejuni GM cells were collected from a BA plate and suspended in 10 mM MgSO4 (Thermo Fisher) to a cell density of approximately 10⁷ CFU/ml. A volume of 500 μl of the cell suspension was added 10⁷ PFU DA10 before adding 5 ml of molten NZCYM top agar (0.6%, VWR Leicestershire, UK) and pouring on top of a NZCYM agar plate.

Bacteriophage CP_F1 was originally isolated from a pig manure sample and was propagated on C. jejuni PT14 (Brathwaite et al., 2013 (link)). All strains, associated plasmids and oligonucleotide PCR primers used in this study are listed in Table 1. The C. jejuni strains were routinely grown on blood agar base No. 2 plates (BA plates; Oxoid) supplemented with 5% horse blood (TCS Biosciences) under microaerobic conditions in either a modular atmosphere controlled cabinet (5% CO₂, 5% O₂, 2% H₂, 88% N₂) or in anaerobic jars using gas replacement (7.3% CO₂, 5.6% O₂, 3.6% H₂, 83.5% N₂) at 42°C. Escherichia coli strain TOP10 (Invitrogen) was used for cloning and cultured aerobically at 37°C on Luria agar plates or in Luria broth containing appropriate antibiotic as required.