ST5136 is a multi-drug resistant and the largest vertically expanding UK wide clone of Campylobacter jejuni

Bruno Silvester Lopes

doi:10.21767/2472-1093-C2-006

ST5136 is a multi-drug resistant and the largest vertically expanding UK wide clone of Campylobacter jejuni

6^th Edition of International Conference on Antibiotics, Antimicrobials and Resistance

October 11-12, 2018 Edinburgh, Scotland

Bruno Silvester Lopes

University of Aberdeen,UK

Posters & Accepted Abstracts: J Infec Dis Treat

Abstract:

Introduction: Campylobacter jejuni and Campylobacter coli are the most common causes of bacterial gastroenteritis in the developed world. The aim of this study was to understand how antibiotics in the farm environment select for antibiotic resistant clones of Campylobacter. The diversity of tetracycline resistant determinants and quinolone resistances conferred by gyrA mutations in Campylobacter isolated from different host reservoirs was assessed. Materials & Methods: DNA from pure cultures of Campylobacter spp. from chicken, cattle, sheep and humans in Grampian region of Scotland was extracted and whole genome sequencing was done using an Illumina HiSeq 2000 sequencer with 100 base paired-end sequencing and the FASTQ paired-end reads were assembled using Velvet. The genomes (4000) were assessed for purity and submitted to the Bacterial Isolate Genome Sequence Database (BIGSdb), where alleles were tagged and the presence of the tetracycline resistance determinant CAMP1698 and the C257T gyrA mutation were identified. Results: Whole genome multilocus sequence typing (MLST) analysis using 136 representative strains isolated from UK identified that ST5136 is a UK wide clone, having emerged from ST464 through substantial genetic recombination. ST5136 was exclusively associated with chicken, turkey and humans and was the most prevalent strain harbouring the tet(O/32/O) 7-like determinant. The most common tetracycline resistant alleles were tet(O/32/O)7 and tet(O/32/O)8, 13. The tet(O/32/O)-7 variant was chromosomally associated in ST5136. 99% (207/209) of CC464 strains were ciprofloxacin resistant and had the C257T gyrA mutation. Conclusion: The tet(O) [Φ-m46.1] and tet(O)-like variants in Campylobacter were closely related. The tet(O/32/O) from human gut bacteria and Campylobacter were also similar in sequence, suggesting the potential for Campylobacter and other species to rapidly evolve through common DNA transfer systems. The increase in resistance to ciprofloxacin and tetracycline in clonally expanding populations of Campylobacter and the usage of these antibiotics in agriculture will be discussed.