Expanded multilocus sequence typing and comparative genomic hybridization of Campylobacter coli isolates from...

Area of Science:

• Microbiology
• Evolutionary Biology
• Genomics

Background:

• Campylobacter coli is an important foodborne pathogen.
• Understanding its evolutionary history and host associations is crucial for public health.
• Genomic diversity and host adaptation mechanisms remain incompletely understood.

Purpose of the Study:

• To investigate the evolutionary history of Campylobacter coli isolates from diverse host origins.
• To identify specific genes within the dispensable genome associated with particular host species.
• To elucidate the roles of common ancestry and horizontal gene transfer in host adaptation.

Main Methods:

• Multilocus sequence typing (MLST) and ClonalFrame analysis of 85 isolates.
• Population genetic analyses using STRUCTURE and Analysis of Molecular Variance (AMOVA).
• Microarray comparative genomic hybridization (CGH) to assess gene content.

Main Results:

• MLST and ClonalFrame analyses suggested host-associated groups for C. coli, with recombination playing a role in diversification.
• Population genetic analyses indicated distinct genetic clustering for swine, chicken/human, duck/wild bird, and turkey isolates.
• AMOVA confirmed host species as a significant factor in genetic variation, while macrogeography did not.
• Microarray CGH identified specific gene combinations associated with particular hosts.

Conclusions:

• Campylobacter coli exhibits host-preferred genetic groups, influenced by both common ancestry and lateral gene transfer.
• Host species is a primary driver of genetic variation in C. coli populations.
• Genomic content varies predictably with host association, offering insights into pathogen adaptation.