Predicting Genetic Traits and Epitope Analysis of apxIVA in Actinobacillus pleuropneumoniae

• Published in: The journal of microbiology 2011, 49(3), , pp.462-468
• Main Authors: Shin, M.K., Seoul National University, Seoul, Republic of Korea, Cha, S.B., Seoul National University, Seoul, Republic of Korea, Lee, W.J., Seoul National University, Seoul, Republic of Korea, Yoo, H.S., Seoul National University, Seoul, Republic of Korea
• Format: Article
• Language: English
• Subjects: Actinobacillus Infections - microbiology; ACTINOBACILLUS PLEUROPNEUMONIAE; Actinobacillus pleuropneumoniae - classification; Actinobacillus pleuropneumoniae - genetics; Actinobacillus pleuropneumoniae - immunology; Actinobacillus pleuropneumoniae - metabolism; Acylation; Amino acids; Animals; ApxIV; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - immunology; Biomedical and Life Sciences; C-Terminus; Conserved sequence; Cytotoxicity; Differential diagnosis; Epitope Mapping; Epitopes; Epitopes, B-Lymphocyte - immunology; Genes; Genetic analysis; Hemorrhage; Hogs; Homology; Hydrophobicity; Immunity; Infections; Life Sciences; Lymphocytes B; Microbiology; Molecular Sequence Data; Nucleotides; Pathogenesis; Phylogeny; Pneumonia; Republic of Korea; RTX toxins; Sequence Analysis, DNA; sequences; Serotypes; Serotyping; Swine Diseases - microbiology; Toxins; Vaccines; Veterinary medicine; Virulence; 생물학
• ISSN: 1225-8873; 1976-3794
• DOI: 10.1007/s12275-011-0449-y

Actinobacillus pleuropneumoniae causes a severe hemorrhagic pneumonia in pigs. Fifteen serotypes of A. pleuropneumoniae express four different Apx toxins that belong to the pore-forming repeats-in-toxin (RTX) group of toxins. ApxIV, which is conserved and up-regulated in vivo, could be an excellent candidate for the development of a protective cross-serotype immunity vaccine, and could aid in the differential diagnosis of diseases caused by A. pleuropneumoniae. We identified and sequenced apxIVA from A. pleuropneumoniae serotype 2 isolated in Korea (Kor-ApxIVA). The Kor-ApxIVA was closely related to Switzerland (AF021919), China (CP000687), and China (6Q332268), showing 98.6%, 98.4%, and 97.2% amino acid homology, respectively. The level of amino acid homology, however, was higher than the nucleotide homology. The structural characteristics of ApxIVA showed RTX proteins, including N-terminal hydrophobic domains, signature sequences for potential acylation sites, and repeated glycine-rich nonapeptides in the C-terminal region of the protein. Thirty glycine-rich nonapeptides with the consensus sequence, L/V-X-G-G-X-G-N/D-D-X, were found in the C-terminus of the Kor-ApxIVA. In addition, the Kor-ApxIVA was predicted for the linear B-cell epitopes and conserved domains with determined peptide sequences. This genetic analysis of the Kor-ApxIVA might be an important foundation for future biological and functional research on ApxIVA.