A Unique Capsule Locus in the Newly Designated Actinobacillus pleuropneumoniae Serovar 16 and Development of a Diagnostic PCR Assay

J Clin Microbiol. 2017 Mar;55(3):902-907. doi: 10.1128/JCM.02166-16. Epub 2017 Jan 4.

Abstract

Actinobacillus pleuropneumoniae causes pleuropneumonia, an economically significant lung disease of pigs. Recently, isolates of A. pleuropneumoniae that were serologically distinct from the previously characterized 15 serovars were described, and a proposal was put forward that they comprised a new serovar, serovar 16. Here we used whole-genome sequencing of the proposed serovar 16 reference strain A-85/14 to confirm the presence of a unique capsular polysaccharide biosynthetic locus. For molecular diagnostics, primers were designed from the capsule locus of strain A-85/14, and a PCR was formulated that differentiated serovar 16 isolates from all 15 known serovars and other common respiratory pathogenic/commensal bacteria of pigs. Analysis of the capsule locus of strain A-85/14 combined with the previous serological data show the existence of a sixteenth serovar-designated serovar 16-of A. pleuropneumoniae.

Keywords: Actinobacillus pleuropneumoniae; PCR; diagnostics; serovar 16.

MeSH terms

  • Actinobacillus Infections / diagnosis
  • Actinobacillus Infections / veterinary*
  • Actinobacillus pleuropneumoniae / classification*
  • Actinobacillus pleuropneumoniae / genetics
  • Animals
  • Bacterial Capsules / genetics*
  • DNA Primers / genetics
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Genetic Loci*
  • Genome, Bacterial
  • Molecular Diagnostic Techniques / methods
  • Pleuropneumonia / microbiology
  • Pleuropneumonia / veterinary
  • Polymerase Chain Reaction / methods*
  • Sequence Analysis, DNA
  • Serogroup*
  • Swine
  • Swine Diseases / diagnosis*

Substances

  • DNA Primers
  • DNA, Bacterial