Format

Send to

Choose Destination
PLoS Pathog. 2018 Dec 7;14(12):e1007453. doi: 10.1371/journal.ppat.1007453. eCollection 2018 Dec.

A genome-wide association analysis reveals a potential role for recombination in the evolution of antimicrobial resistance in Burkholderia multivorans.

Author information

1
Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada.
2
Latner Thoracic Surgery Laboratories, University Health Network, University of Toronto, Toronto, Ontario, Canada.
3
Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
4
Centre for the Analysis of Genome Evolution and Function, University of Toronto, Toronto, Ontario, Canada.
5
Division of Infectious Diseases, Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada.
6
Adult Cystic Fibrosis Clinic, St. Michael's Hospital, Toronto, Ontario, Canada.
7
Department of Pediatric Laboratory Medicine, Division of Microbiology, The Hospital for Sick Children, Toronto, Ontario, Canada.
8
Department of Pediatrics, Division of Infectious Diseases, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
9
Department of Pathology, University Health Network, Toronto, Ontario, Canada.

Abstract

Cystic fibrosis (CF) lung infections caused by members of the Burkholderia cepacia complex, such as Burkholderia multivorans, are associated with high rates of mortality and morbidity. We performed a population genomics study of 111 B. multivorans sputum isolates from one CF patient through three stages of infection including an early incident isolate, deep sampling of a one-year period of chronic infection occurring weeks before a lung transplant, and deep sampling of a post-transplant infection. We reconstructed the evolutionary history of the population and used a lineage-controlled genome-wide association study (GWAS) approach to identify genetic variants associated with antibiotic resistance. We found the incident isolate was basally related to the rest of the strains and more susceptible to antibiotics from three classes (β-lactams, aminoglycosides, quinolones). The chronic infection isolates diversified into multiple, distinct genetic lineages and showed reduced antimicrobial susceptibility to the same antibiotics. The post-transplant reinfection isolates derived from the same source as the incident isolate and were genetically distinct from the chronic isolates. They also had a level of susceptibility in between that of the incident and chronic isolates. We identified numerous examples of potential parallel pathoadaptation, in which multiple mutations were found in the same locus or even codon. The set of parallel pathoadaptive loci was enriched for functions associated with virulence and resistance. Our GWAS analysis identified statistical associations between a polymorphism in the ampD locus with resistance to β-lactams, and polymorphisms in an araC transcriptional regulator and an outer membrane porin with resistance to both aminoglycosides and quinolones. Additionally, these three loci were independently mutated four, three and two times, respectively, providing further support for parallel pathoadaptation. Finally, we identified a minimum of 14 recombination events, and observed that loci carrying putative parallel pathoadaptations and polymorphisms statistically associated with β-lactam resistance were over-represented in these recombinogenic regions.

PMID:
30532201
PMCID:
PMC6300292
DOI:
10.1371/journal.ppat.1007453
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Public Library of Science Icon for PubMed Central
Loading ...
Support Center