Campylobacter jejuni ST50, a pathogen of global importance: A comparative genomic analysis of isolates from Australia, Europe and North America

Abstract

Campylobacter jejuni is the leading cause of bacterial gastroenteritis globally, and infections are often transmitted through consumption of raw or undercooked poultry.Campylobacter jejuni ST50 is among the top ten sequence types (STs) reported in the collected isolates listed at PubMLST records from poultry, food and clinical sources for Asia, Europe, North America, Oceania and South America. This study was designed to determine the most commonly reported C. jejuni STs globally using the PubMLST database and assess similarities between genomes of C. jejuni ST50 isolates from geographically distinct locations. To gain a better understanding of C. jejuni diversity, we compared draft genome sequences of 182 ST50 isolates recovered from retail or caecal poultry samples in Oceania, Europe and North America that were collected over a period of 9 years (2010 to 2018). Overall, phylogenetic analysis revealed that isolates from geographically distinct locations tended to cluster based on the continent where the sample was collected. Among ST50 isolates from Europe and North America, we identified resistance determinants associated with phenotypic resistance to beta-lactams (EU: 55%; GB: 43.1%), tetracyclines (CA: 77.3%; EU: 37.5%; GB: 9.8%; US: 43.5%) and fluoroquinolones (EU: 60.0%; GB: 15.7%); no resistance determinants were identified in isolates from Australia. In general, the majority of the virulence genes, with rare exceptions such as wlaN, cj1138, hddA and rfbC, were evenly distributed throughout the genomes of all ST50 isolates in this study.Genomic-based characterization of C. jejuni ST50 isolates from poultry on three continents highlighted that geographically distinct isolates have evolved independently but only represent a glimpse into the diversity of C. jejuni.

The Distribution of Campylobacter jejuni Virulence Genes in Genomes Worldwide Derived from the NCBI Pathogen Detection Database

“…It was the second most common ST in North America and the sixth most common ST in South America. This sequence type has been recently characterized in C. jejuni genomes from North America, Europe, and Australia, highlighting its importance as a global pathogen [16]. The ST50 distribution presented here corroborates with Wallace et al [16], who showed that the ST50 is among the top ten commonly reported STs within the more than 77,000 sequences deposited in the PubMLST in all continents except Africa.…”

“…This sequence type has been recently characterized in C. jejuni genomes from North America, Europe, and Australia, highlighting its importance as a global pathogen [16]. The ST50 distribution presented here corroborates with Wallace et al [16], who showed that the ST50 is among the top ten commonly reported STs within the more than 77,000 sequences deposited in the PubMLST in all continents except Africa. Interestingly, none of the host generalist sequence types ST21, ST45, and ST48 were reported top in Africa, Asia, and South America, although the chicken specialist ST353 [38][39][40] was most frequently identified in Africa and South America.…”

“…The genetic diversity of these species is reflected in the more than 11,800 STs registered on the PubMLST database. Notably, more than 8000 C. jejuni sequence types were registered by 2020 [16]. Certainly, the determination of C. jejuni STs is a valuable resource to the scientific community as a whole for the genotyping investigation of this critical and yet incompletely understood pathogen.…”

Local accessory gene sharing among Egyptian Campylobacter potentially promotes the spread of antimicrobial resistance

“…Geographical differences have been noted in ST-21 CC [41,78,[110][111][112][113]. ST-21 CC isolates are among the most common C. jejuni genotypes isolated worldwide, with one quarter of C. jejuni isolates recorded in the pubMLST database are ST-21 CC.…”

Local accessory gene sharing drives lineage-specific acquisition of antimicrobial resistance in Egyptian Campylobacter spp.

“…Geographical differences have been noted in ST-21CC (Kärenlampi et al, 2007;Kovanen et al, 2014;Olkkola et al, 2016;Pascoe et al, 2017;Wallace et al, 2021). ST-21 CC isolates are among the most common C. jejuni genotypes isolated worldwide, with one quarter of C. jejuni isolates recorded in the pubMLST database are ST21 CC.…”