Campylobacter selective supplement skirrow

Bacterial cultures were maintained as previously described [17 (link),18 (link)]. B. infantis was stored in de Man–Rogosa–Sharpe (MRS) (Difco, Sparks, MD, USA) broth containing 50% glycerol at −80 °C. The strain was cultured twice in MRS media supplemented with L-cysteine (0.05% w/v) (Merck, Dannstadt, Germany) prior to use, and was routinely grown overnight at 37 °C under anaerobic conditions generated using an Anaerocult A system (Merck, Dannstadt, Germany).
C. jejuni 81–176 was stored in Mueller Hinton broth (Oxoid, Ireland c/o Fannin Healthcare, Dublin, Ireland) containing 50% glycerol at −80 °C and cultured directly from storage onto Mueller-Hinton agar plates. The pathogen was grown under microaerophilic conditions generated using CampyGen gas packs (Oxoid), for 48 h at 37 °C as previously described [19 (link),22 (link)]. Prior to pathogen inhibition assays, C. jejuni 81–176 was grown on Mueller-Hinton agar and then transferred to biphasic media in 25 cm² tissue culture flasks (Corning, New York, NY, USA) consisting of Mueller-Hinton agar supplemented with Campylobacter selective supplement (Skirrow), (Oxoid) and 6 mL of McCoy’s 5A media (Merck) supplemented with 2% fetal bovine serum (FBS). The flask was then incubated for 24 h under microaerophilic conditions at 37 °C.

Campylobacter jejuni 81–176 (C. jejuni) is a well-characterized, mobile flagellated invasive strain which has been used in many previous studies [17 (link),18 (link)]. The pathogen was stored in Mueller–Hinton broth (Oxoid, Ireland c/o Fannin Healthcare, Dublin, Ireland) containing 50% glycerol at −80 °C and cultured directly from storage onto Mueller–Hinton agar plates. The pathogen was grown under microaerophilic conditions generated using CampyGen gas packs (Oxoid), for 48 h at 37 °C. Prior to pathogen inhibition assays, C. jejuni 81–176 was grown on Mueller–Hinton agar and then transferred to biphasic media in 25 cm² tissue culture flasks (Corning, NY, USA) consisting of Mueller–Hinton agar supplemented with Campylobacter selective supplement (Skirrow), (Oxoid) and 6 mL of McCoy′s 5A media (Merck) supplemented with 2% FBS. The flask was then incubated for 24 h under microaerophilic conditions at 37 °C.

Helicobacter suis strain HS1 and HS5 were cultured in biphasic Brucella culture plates (BD BBL, 211086) containing 20% fetal bovine serum (FBS) (HyClone, SH30071.01), Vitox supplement (Oxoid, SR0090H), Skirrow Campylobacter selective supplement (Oxoid, SR0069E), and 5 mg/L amphotericin B. The pH of the agar was adjusted to 5. One mL sterile brucella broth (pH 5) was added onto the agar surface. The bacteria were cultured under microaerobic conditions at 37°C [37 (link)].