Characterization of the omlA gene from different serotypes of Actinobacillus pleuropneumoniae: a new insight into an old approach

Abstract

The OmlA protein is a virulence factor of Actinobacillus pleuropneumoniae, an important pathogen in pigs. The polymorphisms present in the omlA gene sequence of 15 reference serotypes of A. pleuropneumoniae and non-serotypable isolates were assessed to determine the possible evolutionary relationship among them and to validate the importance of this gene as a molecular marker for the characterization of this bacterium. Divergence among the 15 serotypes of A. pleuropneumoniae probably resulted initially from two major evolutionary events that led to subsequent differentiation into nine groups. This differentiation makes it possible to characterize most of the serotypes by using bionformatics, thereby avoiding problems with immunological cross-reactivity. A conserved α-helix common to all the serotypes was most likely involved in connecting the protein to the outer membrane and acting as a signal peptide. A previously unknown gene duplication was also identified and could contribute to the genetic variability that makes it difficult to serotype some isolates. Our data support the importance of the omlA gene in the biology of A. pleuropneumoniae and provide a new area of research into the OmlA protein.

Identification and characterization of a novel stress-responsive outer membrane protein Lip40 from Actinobacillus pleuropneumoniae

“…However, the pathogenesis of A. pleuropneumoniae lipoproteins has rarely been examined. Most such studies have focused on their immunogenicity and vaccine potential, including studies of TbpB [ 26 – 28 ] and OmlA [ 29 , 30 ]. These proteins were shown to be immunoprotective and important vaccine components (PleuroStar APP, Novartis Animal Health Inc., Switzerland).…”

Genetic variability in isolates of Chromobacterium violaceum from pulmonary secretion, water, and soil

“…Polymorphisms in pathogenicity and virulence factor genes have been subjected to widespread molecular analysis (Nightingale et al, 2005;González-Escalona et al, 2008;Rossi et al, 2013). In this study, the type-strain ATCC 12472 generated a 587-bp PCR fragment, as expected, for the yscD gene.…”

Pathogenesis and Prevention of Porcine Contagious Pleuropneumonia

“…The morbidity was generally 8.5-100% and the mortality was about 0.4-100%. Acute pleuropneumonia is characterized of dyspnea, frequent standing or sitting posture, foam-like secretions on the nose and mouth, blue-purple skin on the ears, nose and extremities, temperature up to 41.5℃, and high mortality (Rossic et al 2013). Cellulosic necrotizing tinea plantar pneumonia is a typical symptom of chronic pleuropneumonia.…”