Format

Send to

Choose Destination
Microbiology. 2015 Mar;161(Pt 3):580-92. doi: 10.1099/mic.0.000035. Epub 2015 Jan 27.

Novel, host-restricted genotypes of Bordetella bronchiseptica associated with phocine respiratory tract isolates.

Author information

1
USDA, Agricultural Research Service, National Animal Disease Center, Ruminant Diseases and Immunology Research Unit, 1920 Dayton Avenue, Ames, IA 50010, USA karen.register@ars.usda.gov.
2
The Pennsylvania State University, Department of Veterinary and Biomedical Sciences, W-213 Millennium Science Complex, University Park, PA 16802, USA.
3
Scottish Marine Animal Stranding Scheme SAC Consulting Veterinary Services, Drummondhill, Stratherrick Road, Inverness IV2 4JZ, UK.

Abstract

During a succession of phocine morbillivirus outbreaks spanning the past 25 years, Bordetella bronchiseptica was identified as a frequent secondary invader and cause of death. The goal of this study was to evaluate genetic diversity and the molecular basis for host specificity among seal isolates from these outbreaks. MLST and PvuII ribotyping of 54 isolates from Scottish, English or Danish coasts of the Atlantic or North Sea revealed a single, host-restricted genotype. A single, novel genotype, unique from that of the Atlantic and North Sea isolates, was found in isolates from an outbreak in the Caspian Sea. Phylogenetic analysis based either on MLST sequence, ribotype patterns or genome-wide SNPs consistently placed both seal-specific genotypes within the same major clade but indicates a distinct evolutionary history for each. An additional isolate from the intestinal tract of a seal on the south-west coast of England has a genotype otherwise found in rabbit, guinea pig and pig isolates. To investigate the molecular basis for host specificity, DNA and predicted protein sequences of virulence genes that mediate host interactions were used in comparisons between a North Sea isolate, a Caspian Sea isolate and each of their closest relatives as inferred from genome-wide SNP analysis. Despite their phylogenetic divergence, fewer nucleotide and amino acid substitutions were found in comparisons of the two seal isolates than in comparisons with closely related strains. These data indicate isolates of B. bronchiseptica associated with respiratory disease in seals comprise unique, host-adapted and highly clonal populations.

PMID:
25627438
PMCID:
PMC4811649
DOI:
10.1099/mic.0.000035
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Ingenta plc Icon for PubMed Central
Loading ...
Support Center