23S rRNA mutation A2074C conferring high-level macrolide resistance and fitness cost in Campylobacter jejuni.
To examine the development of macrolide resistance in Campylobacter jejuni and assess the fitness of the macrolide-resistant mutants, two macrolide-susceptible C. jejuni strains, American Type Culture Collection (ATCC) 33291 and H1, from different geographic areas were exposed to tylosin in vitro. Multiple mutant strains were obtained from the selection. Most of the high-level macrolide-resistant strains derived from the selection exhibited the A2074C transversion in all three copies of 23S rRNA and displayed strong stability in the absence of antibiotic selection pressure. The competition experiments demonstrated that the strains containing the A2074C transversion imposed a fitness cost in competition mixtures. In addition, the fitness cost of the mutation was not ameliorated after approximately 500 generations of evolution under laboratory conditions. These findings indicate that the A2074C transversion in C. jejuni is not only correlated with stable and high-level macrolide resistance but also associated with a fitness cost.
National Reference Laboratory of Veterinary Drug Residues/MOA Key Laboratory of Food Safety Evaluation, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, People's Republic of China.
Haihong
H
Hao
Menghong
M
Dai
Yulian
Y
Wang
Dapeng
D
Peng
Zhenli
Z
Liu
Zonghui
Z
Yuan
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016123:Campylobacter jejuni / Q000187:drug effects* / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004917:Erythromycin / Q000494:pharmacology; D018942:Macrolides / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D009154:Mutation; D012329:RNA, Bacterial / Q000235:genetics; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D015645:Tylosin / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D018942:Macrolides; D012329:RNA, Bacterial; D012338:RNA, Ribosomal, 23S; D004917:Erythromycin; D015645:Tylosin