title: Predicting genetic traits and epitope analysis of apxIVA in Actinobacillus pleuropneumoniae.
abstract: 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 (GQ332268), 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.
authors: Department of Infectious Disease, College of Veterinary Medicine and Brain Korea 21 Program for Veterinary Science, Seoul National University, Seoul, 151-742, Republic of Korea.
authors: Min-Kyoung
authors: MK
authors: Shin
authors: Seung-Bin
authors: SB
authors: Cha
authors: Won-Jung
authors: WJ
authors: Lee
authors: Han Sang
authors: HS
authors: Yoo
mesh_terms: D000189:Actinobacillus Infections / Q000382:microbiology*; D016977:Actinobacillus pleuropneumoniae / Q000145:classification / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D000818:Animals; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D018604:Epitope Mapping; D018985:Epitopes, B-Lymphocyte / Q000276:immunology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D056910:Republic of Korea; D017422:Sequence Analysis, DNA; D012703:Serotyping; D013553:Swine Diseases / Q000382:microbiology
chemical_list: C122177:ApxIVA protein, Actinobacillus pleuropneumoniae; D001426:Bacterial Proteins; D018985:Epitopes, B-Lymphocyte