Tetracycline resistance transmission in Campylobacter is promoted at temperatures resembling the avian reservoir

• Published in: Veterinary microbiology Vol. 244; p. 108652
• Main Authors: Cuevas-Ferrando, E., Guirado, P., Miró, E., Iglesias-Torrens, Y., Navarro, F., Alioto, T.S., Gómez-Garrido, J., Madrid, C., Balsalobre, C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2020; Elsevier BV
• Subjects: Animals; Anti-Bacterial Agents - pharmacology; Antibiotic resistance; Antibiotics; Body Temperature; Body Temperature Regulation; Campylobacter; Campylobacter - drug effects; Campylobacter - pathogenicity; Campylobacteriosis; Chickens - microbiology; Clinical isolates; Conjugation; Conjugation, Genetic; Disease Reservoirs - microbiology; Disease Reservoirs - veterinary; DNA, Bacterial - genetics; Food contamination; Gastroenteritis; Gastrointestinal tract; Heat resistance; High temperature; Humans; Meat; Microbial Sensitivity Tests; Mimicry; Plasmid conjugation; Plasmids; Poultry; Temperature regulation; Tetracycline - pharmacology; Tetracycline Resistance; Thermoregulation; Transcription; Temperature regulation; Tetracycline resistance; Plasmid conjugation; Campylobacter
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2020.108652

•Plasmid conjugation of tet(O) carrying plasmids in Campylobacter is thermoregulated.•Conjugation of tet(O) carrying plasmids is promoted at high temperature.•Transcriptional expression of putative conjugative genes is temperature dependent. Campylobacter is the causal agent of campylobacteriosis in humans, a self-limiting gastroenteritis. Campylobacteriosis is a zoonosis, commonly transmitted from contaminated chicken meat by either direct consumption or cross contamination during food manipulation. Presence of plasmids encoding for resistance to antibiotics such as tetracycline is common among Campylobacter isolates. In this report, we studied the effect of the temperature in the conjugation frequency of several tet(O) carrying plasmids, providing tetracycline resistance to the recipient cells. The conjugation frequency from donor cells carrying three previously characterized plasmids (pCjA13, pCjA9 and pTet) and from two clinical isolates was determined. Two temperatures, 37 and 42 °C, mimicking the conditions encountered by C. jejuni in the human and broiler chicken gastrointestinal tracts, respectively, were assessed. Our results clearly indicate that the conjugation process is promoted at high temperature. Accordingly, the transcriptional expression of some putative conjugative apparatus genes is thermoregulated, being induced at 42 °C. The two plasmids present in the clinical isolates were sequenced and assembled. Both plasmids are highly related among them and to the pTet plasmid. The high identity of the genes putatively involved in the conjugation process among the plasmids is in agreement with the similar behavior regarding the temperature dependency of the conjugative process. This report suggest that conjugation of plasmids carrying antibiotic resistance genes occurs preferentially at temperatures that resemble the gastrointestinal tract of birds, the main reservoir of C. jejuni.