1
|
Stancheva SG, Frömbling J, Sassu EL, Hennig-Pauka I, Ladinig A, Gerner W, Grunert T, Ehling-Schulz M. Proteomic and immunoproteomic insights into the exoproteome of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia. Microb Pathog 2022; 172:105759. [PMID: 36087692 DOI: 10.1016/j.micpath.2022.105759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 10/31/2022]
Abstract
Porcine pleuropneumonia caused by Actinobacillus pleuropneumoniae affects pig health status and the swine industry worldwide. Despite the extensive number of studies focused on A. pleuropneumoniae infection and vaccine development, a thorough analysis of the A. pleuropneumoniae exoproteome is still missing. Using a complementary approach of quantitative proteomics and immunoproteomics we gained an in-depth insight into the A. pleuropneumoniae serotype 2 exoproteome, which provides the basis for future functional studies. Label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed 593 exoproteins, of which 104 were predicted to be virulence factors. The RTX toxins ApxIIA and ApxIIIA -were found to be the most abundant proteins in the A. pleuropneumoniae serotype 2 exoproteome. Furthermore, the ApxIVA toxin was one of the proteins showing the highest abundance, although ApxIVA is commonly assumed to be expressed exclusively in vivo. Our study revealed several antigens, including proteins with moonlight functions, such as the elongation factor (EF)-Tu, and proteins linked to specific metabolic traits, such as the maltodextrin-binding protein MalE, that warrant future functional characterization and might present potential targets for novel therapeutics and vaccines. Our Ig-classes specific serological proteome analysis (SERPA) approach allowed us to explore the development of the host humoral immune response over the course of the infection. These SERPAs pinpointed proteins that might play a key role in virulence and persistence and showed that the immune response to the different Apx toxins is distinct. For instance, our results indicate that the ApxIIIA toxin has properties of a thymus-independent antigen, which should be studied in more detail.
Collapse
Affiliation(s)
- Stelli G Stancheva
- Institute of Microbiology, Department for Pathobiology, University of Veterinary Medicine Vienna, Austria
| | - Janna Frömbling
- Institute of Microbiology, Department for Pathobiology, University of Veterinary Medicine Vienna, Austria
| | - Elena L Sassu
- University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Austria
| | - Isabel Hennig-Pauka
- Field Station for Epidemiology, University of Veterinary Medicine Hannover, Bakum, Germany
| | - Andrea Ladinig
- University Clinic for Swine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Austria
| | - Wilhelm Gerner
- Institute of Immunology, Department of Pathobiology, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Tom Grunert
- Institute of Microbiology, Department for Pathobiology, University of Veterinary Medicine Vienna, Austria
| | - Monika Ehling-Schulz
- Institute of Microbiology, Department for Pathobiology, University of Veterinary Medicine Vienna, Austria.
| |
Collapse
|
2
|
Petry AL, Patience JF, Koester LR, Huntley NF, Bedford MR, Schmitz-Esser S. Xylanase modulates the microbiota of ileal mucosa and digesta of pigs fed corn-based arabinoxylans likely through both a stimbiotic and prebiotic mechanism. PLoS One 2021; 16:e0246144. [PMID: 33503052 PMCID: PMC7840016 DOI: 10.1371/journal.pone.0246144] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 01/14/2021] [Indexed: 01/03/2023] Open
Abstract
The experimental objective was to characterize the impact of insoluble corn-based fiber, xylanase, and an arabinoxylan-oligosaccharide on ileal digesta and mucosa microbiome of pigs. Three replicates of 20 gilts were blocked by initial body weight, individually-housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF), a 30% corn bran high-fiber control (HF), HF+100 mg/kg xylanase (HF+XY), and HF+50 mg/kg arabinoxylan oligosaccharide (HF+AX). Gilts were fed their respective treatments for 46 days. On day 46, pigs were euthanized and ileal digesta and mucosa were collected. The V4 region of the 16S rRNA was amplified and sequenced, generating a total of 2,413,572 and 1,739,013 high-quality sequences from the digesta and mucosa, respectively. Sequences were classified into 1,538 mucosa and 2,495 digesta operational taxonomic units (OTU). Hidden-state predictions of 25 enzymes were made using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUST2). Compared to LF, HF increased Erysipelotrichaceae_UCG-002, and Turicibacter in the digesta, Lachnospiraceae_unclassified in the mucosa, and decreased Actinobacillus in both (Q<0.05). Relative to HF, HF+XY increased 19 and 14 of the 100 most abundant OTUs characterized from digesta and mucosa, respectively (Q<0.05). Notably, HF+XY increased the OTU_23_Faecalibacterium by nearly 6 log2-fold change, compared to HF. Relative to HF, HF+XY increased genera Bifidobacterium, and Lactobacillus, and decreased Streptococcus and Turicibacter in digesta (Q<0.05), and increased Bifidobacterium and decreased Escherichia-Shigella in the mucosa (Q<0.05). Compared to HF, HF+AX increased 5 and 6 of the 100 most abundant OTUs characterized from digesta and mucosa, respectively, (Q<0.05), but HF+AX did not modulate similar taxa as HF+XY. The PICRUST2 predictions revealed HF+XY increased gene-predictions for enzymes associated with arabinoxylan degradation and xylose metabolism in the digesta, and increased enzymes related to short-chain fatty acid production in the mucosa. Collectively, these data suggest xylanase elicits a stimbiotic and prebiotic mechanism.
Collapse
Affiliation(s)
- Amy L Petry
- Department of Animal Science, Iowa State University, Ames, Iowa, United States of America
| | - John F Patience
- Department of Animal Science, Iowa State University, Ames, Iowa, United States of America.,Iowa Pork Industry Center, Iowa State University, Ames, Iowa, United States of America
| | - Lucas R Koester
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, Iowa, United States of America
| | - Nichole F Huntley
- Department of Animal Science, Iowa State University, Ames, Iowa, United States of America
| | | | - Stephan Schmitz-Esser
- Department of Animal Science, Iowa State University, Ames, Iowa, United States of America
| |
Collapse
|
3
|
Turni C, Wu Y, Omaleki L, Giang N, Blackall PJ, Christensen H. Glaesserella australis sp. nov., isolated from the lungs of pigs. Int J Syst Evol Microbiol 2020; 70:3686-3692. [PMID: 32416742 DOI: 10.1099/ijsem.0.004221] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Twenty-nine isolates of an unknown haemophilic organism were isolated from the lungs of pigs from 14 farms in Australia. Phylogenetic analyses based on the 16S rRNA gene, recN and rpoA showed a monophyletic group that was most closely related to Glaesserella parasuis and [Actinobacillus] indolicus. Whole genome sequence analysis indicated that the Glaesserella parasuis and this group, using the type strain HS4635T for comparison, showed a similarity of 30.9 % DNA-DNA renaturation. The isolates were Gram-stain-negative, NAD-dependent, CAMP-negative and were oxidase-positive, catalase-negative and produced indole but not urease. The isolates could be separated from all currently recognized haemophilic and non-haemophilic members of the family Pastuerellaceae. Key phenotypic properties were the production of indole, the lack of urease activity, production of β-galactosidase but not α-fucosidase, acid formation from (-)-d-arabinose, (+)-d-galactose, maltose and trehalose and a failure to produce acid from (-)-d-mannitol. Taken together, these data indicate that the isolates belong to a novel species for which the name Glaesserella australis sp. nov. is proposed. The type strain is HS4635T (=CCUG 71931T and LMG 30645T).
Collapse
Affiliation(s)
- Conny Turni
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Yunchen Wu
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Lida Omaleki
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Nhan Giang
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - P J Blackall
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, Queensland 4067, Australia
| | - Henrik Christensen
- Department of Veterinary and Animal Sciences, University of Copenhagen, 4 Stigbøjlen, DK-1870 Frederiksberg C, Denmark
| |
Collapse
|
4
|
Draft Genome Sequences of the Type Strains of Actinobacillus indolicus (46K2C) and Actinobacillus porcinus (NM319), Two NAD-Dependent Bacterial Species Found in the Respiratory Tract of Pigs. Microbiol Resour Announc 2020; 9:9/1/e00716-19. [PMID: 31896621 PMCID: PMC6940273 DOI: 10.1128/mra.00716-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report here the draft genome sequences of the type strains of Actinobacillus indolicus (46K2C) and Actinobacillus porcinus (NM319). These NAD-dependent bacterial species are frequently found in the upper respiratory tract of pigs and are occasionally associated with lung pathology. We report here the draft genome sequences of the type strains of Actinobacillus indolicus (46K2C) and Actinobacillus porcinus (NM319). These NAD-dependent bacterial species are frequently found in the upper respiratory tract of pigs and are occasionally associated with lung pathology.
Collapse
|
5
|
Frey J. RTX Toxins of Animal Pathogens and Their Role as Antigens in Vaccines and Diagnostics. Toxins (Basel) 2019; 11:toxins11120719. [PMID: 31835534 PMCID: PMC6950323 DOI: 10.3390/toxins11120719] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 12/03/2019] [Accepted: 12/04/2019] [Indexed: 01/19/2023] Open
Abstract
Exotoxins play a central role in the pathologies caused by most major bacterial animal pathogens. The large variety of vertebrate and invertebrate hosts in the animal kingdom is reflected by a large variety of bacterial pathogens and toxins. The group of repeats in the structural toxin (RTX) toxins is particularly abundant among bacterial pathogens of animals. Many of these toxins are described as hemolysins due to their capacity to lyse erythrocytes in vitro. Hemolysis by RTX toxins is due to the formation of cation-selective pores in the cell membrane and serves as an important marker for virulence in bacterial diagnostics. However, their physiologic relevant targets are leukocytes expressing β2 integrins, which act as specific receptors for RTX toxins. For various RTX toxins, the binding to the CD18 moiety of β2 integrins has been shown to be host specific, reflecting the molecular basis of the host range of RTX toxins expressed by bacterial pathogens. Due to the key role of RTX toxins in the pathogenesis of many bacteria, antibodies directed against specific RTX toxins protect against disease, hence, making RTX toxins valuable targets in vaccine research and development. Due to their specificity, several structural genes encoding for RTX toxins have proven to be essential in modern diagnostic applications in veterinary medicine.
Collapse
Affiliation(s)
- Joachim Frey
- Vetsuisse Facutly, University of Bern, 3012 Bern, Switzerland
| |
Collapse
|
6
|
Comparative Genomics of the First and Complete Genome of " Actinobacillus porcitonsillarum" Supports the Novel Species Hypothesis. Int J Genomics 2018; 2018:5261719. [PMID: 30363939 PMCID: PMC6186353 DOI: 10.1155/2018/5261719] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 08/12/2018] [Indexed: 11/25/2022] Open
Abstract
“Actinobacillus porcitonsillarum” is considered a nonpathogenic member of the Pasteurellaceae family, which phenotypically resembles the pathogen Actinobacillus pleuropneumoniae. Previous studies suggested that “A. porcitonsillarum” may represent a new species closely related to Actinobacillus minor, yet no full genome has been sequenced so far. We implemented the Oxford Nanopore and Illumina sequencing technologies to obtain the highly accurate and complete genome sequence of the “A. porcitonsillarum” strain 9953L55. After validating our de novo assembly strategy by comparing the A. pleuropneumoniae S4074T genome sequence obtained by Oxford Nanopore Technology combined with Illumina reads with a PacBio-sequenced S4074T genome from the NCBI database, we performed comparative analyses of the 9953L55 genome with the A. minor type strain NM305T, A. minor strain 202, and A. pleuropneumoniae S4074T. The 2,263,191 bp circular genome of 9953L55 consisted of 2168 and 2033 predicted genes and proteins, respectively. The lipopolysaccharide cluster resembled the genetic organization of A. pleuropneumoniae serotypes 1, 9, and 11, possibly explaining the positive reactions observed previously in serotyping tests. In contrast to NM305T, we confirmed the presence of a complete apxIICABD operon in 9953L55 and 202 accounting for their hemolytic phenotype and Christie-Atkins-Munch-Petersen (CAMP) reaction positivity. Orthologous gene cluster analysis provided insight into the differential ability of strains of the A. minor/“porcitonsillarum” complex and A. pleuropneumoniae to ferment lactose, raffinose, trehalose, and mannitol. The four strains showed distinct and shared transposable elements, CRISPR/Cas systems, and integrated prophages. Genome comparisons based on average nucleotide identity and in silico DNA-DNA hybridization confirmed the close relationship among strains belonging to the A. minor/“porcitonsillarum” complex compared to other Actinobacillus spp., but also suggested that 9953L55 and 202 belong to the same novel species closely related to A. minor, namely, “A. porcitonsillarum.” Recognition of the taxon as a separate species would improve diagnostics and control strategies of pig pleuropneumonia.
Collapse
|
7
|
Hoeltig D, Nietfeld F, Strutzberg-Minder K, Rohde J. Evaluation of the predictive value of tonsil examination by bacteriological culture for detecting positive lung colonization status of nursery pigs exposed to Actinobacillus pleuropneumoniae by experimental aerosol infection. BMC Vet Res 2018; 14:211. [PMID: 29954395 PMCID: PMC6022346 DOI: 10.1186/s12917-018-1542-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 06/24/2018] [Indexed: 11/27/2022] Open
Abstract
Background Actinobacillus (A.) pleuropneumoniae is the causative agent of porcine pleuropneumonia. For control of the disease the detection of sub-clinically infected pigs is of major importance to avoid transmitting of subclinical infections. One method recommended is the testing of tonsillar samples for the presence of A. pleuropneumoniae. This is routinely done by PCR techniques. However, based upon PCR susceptibility testing and monitoring of resistance development is impossible. Therefore, in this study the informative values of bacteriological culture of tonsilar samples for the colonisation status of pigs were tested. In total, 163 German Landrace nursery pigs were experimentally exposed to A. pleuropneumoniae serotype 7 by aerosol and the rate of isolation from lung tissue and tonsils and the corresponding degree of lung lesions were investigated. Results Overall a significant correlation (p < 0.001) between degree of clinical disease, degree of lung alterations and degree of A. pleuropneumoniae isolation from tonsillar and lung tissue after exposure was detected. Of these animals tested, 74.8% were tested positive in tonsillar and lung samples, 7.4% remained completely negative and in 4.3% the tonsils were tested positive despite negative isolation results from lung tissue. In 13.5% of the pigs A. pleuropneumoniae could be isolated in lung tissue but not in tonsillar samples. In 36.4% of these animals a heavy colonization of the lungs and in 40.9% moderate to severe lung alterations were proven. Hence, the diagnostic sensitivity for the detection of a positive colonization status of the pigs by bacterial culture examination of tonsillar samples was 84.7%, the diagnostic specificity was 66.7% and the predictive values were 94.6% (positive) and 35.3% (negative). The overall sensitivity for A. pleuropneumoniae exposure was 78.2% (tonsils) and 88.0% (lung tissue). Conclusions In conclusion, tonsil examination alone for the detection of a positive colonization status of pigs performed might lead to false negative results as lungs might be heavily colonized despite negative tonsillar isolation results. Therefore culture of tonsillar samples should not be the sole test for the confirmation of a pigs’ status but used in combination with methods also evaluating the colonization status of the lower respiratory tract.
Collapse
Affiliation(s)
- Doris Hoeltig
- Clinic for Swine and Small Ruminants, Forensic Medicine and Ambulatory Service, University of Veterinary Medicine, Foundation, Bischofsholer Damm 15, D-30173, Hannover, Germany.
| | - Florian Nietfeld
- Clinic for Swine, Department of Veterinary Medicine, Justus-Liebig-University Giessen, Frankfurter Str. 112, D- 35392, Giessen, Germany
| | | | - Judith Rohde
- Institute for Microbiology, University of Veterinary Medicine, Foundation, Bischofsholer Damm 15, D-30173, Hannover, Germany
| |
Collapse
|
8
|
Abstract
The introduction into a naïve herd of animals sub-clinically infected with Actinobacillus pleuropneumoniae (App) is frequently the cause of clinical pleuropneumonia and the identification of such infected herds is a priority in the control of disease. Different serological tests for App have been developed and a number of these are routinely used. Some are species-specific whereas others identify more specifically the serotype/serogroup involved which requires updated information about important serotypes recovered from diseased pigs in a given area/country. Serotyping methods based on molecular techniques have been developed lately and are ready to be used by most diagnostic laboratories. When non-conclusive serological results are obtained, direct detection of App from tonsils is sometimes attempted. This review addresses different techniques and approaches used to monitor herds sub-clinically infected by this important pathogen.
Collapse
Affiliation(s)
- Marcelo Gottschalk
- Department of Pathology and Microbiology, Swine and Poultry Infectious Disease Center (CRIPA), Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada J2S 2M2.
| |
Collapse
|
9
|
Yu S, Zuo Z, Cui H, Li M, Peng X, Zhu L, Zhang M, Li X, Xu Z, Gan M, Deng J, Fang J, Ma J, Su S, Wang Y, Shen L, Ma X, Ren Z, Wu B, Hu Y. Transcriptional profiling of hilar nodes from pigs after experimental infection with Actinobacillus pleuropneumoniae. Int J Mol Sci 2013; 14:23516-32. [PMID: 24351863 PMCID: PMC3876060 DOI: 10.3390/ijms141223516] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/12/2013] [Accepted: 11/15/2013] [Indexed: 11/16/2022] Open
Abstract
The gram-negative bacterium Actinobacillus pleuropneumoniae (APP) is an inhabitant of the porcine upper respiratory tract and the causative agent of porcine pleuropneumonia (PP). In recent years, knowledge about the proinflammatory cytokine and chemokine gene expression that occurs in lung and lymph node of the APP-infected swine has been advanced. However, systematic gene expression profiles on hilar nodes from pigs after infection with Actinobacillus pleuropneumoniae have not yet been reported. The transcriptional responses were studied in hilar nodes (HN) from swine experimentally infected with APP and the control groupusing Agilent Porcine Genechip, including 43,603 probe sets. 9,517 transcripts were identified as differentially expressed (DE) at the p ≤ 0.01 level by comparing the log2 (normalized signal) of the two groups named treatment group (TG) and controls (CG). Eight hundred and fifteen of these DE transcripts were annotated as pig genes in the GenBank database (DB). Two hundred and seventy-two biological process categories (BP), 75 cellular components and 171 molecular functions were substantially altered in the TG compared to CG. Many BP were involved in host immune responses (i.e., signaling, signal transmission, signal transduction, response to stimulus, oxidation reduction, response to stress, immune system process, signaling pathway, immune response, cell surface receptor linked signaling pathway). Seven DE gene pathways (VEGF signaling pathway, Long-term potentiation, Ribosome, Asthma, Allograft rejection, Type I diabetes mellitus and Cardiac muscle contraction) and statistically significant associations with host responses were affected. Many cytokines (including NRAS, PI3K, MAPK14, CaM, HSP27, protein phosphatase 3, catalytic subunit and alpha isoform), mediating the proliferation and migration of endothelial cells and promoting survival and vascular permeability, were activated in TG, whilst many immunomodulatory cytokines were suppressed. The significant changes in the expression patterns of the genes, GO terms, and pathways, led to a decrease of antigenic peptides with antigen presenting cells presented to T lymphocytes via the major histocompatibility complex, and alleviated immune response induced APP of HN. The immune response ability of HN in the APP-infected pigs was weakened; however, cell proliferation and migration ability was enhanced.
Collapse
Affiliation(s)
- Shumin Yu
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Zhicai Zuo
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Hengmin Cui
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +86-136-0826-4628; Fax: +86-835-2882340
| | - Mingzhou Li
- College of Animal Science and Technology, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (M.L.); (M.Z.); (X.L.); (J.M.)
| | - Xi Peng
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Ling Zhu
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Ming Zhang
- College of Animal Science and Technology, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (M.L.); (M.Z.); (X.L.); (J.M.)
| | - Xuewei Li
- College of Animal Science and Technology, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (M.L.); (M.Z.); (X.L.); (J.M.)
| | - Zhiwen Xu
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Meng Gan
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Junliang Deng
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Jing Fang
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Jideng Ma
- College of Animal Science and Technology, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (M.L.); (M.Z.); (X.L.); (J.M.)
| | - Shengqun Su
- Library of Sichuan Agricultural University, Ya’an 625014, China; E-Mail:
| | - Ya Wang
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Liuhong Shen
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Xiaoping Ma
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Zhihua Ren
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Bangyuan Wu
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| | - Yanchun Hu
- College of Veterinary Medicine, Sichuan Agricultural University, Ya’an 625014, China; E-Mails: (S.Y.); (Z.Z.); (X.P.); (L.Z.); (Z.X.); (M.G.); (J.D.); (J.F.); (Y.W.); (L.S.); (X.M.); (Z.R.); (B.W.); (Y.H.)
- Laboratory of Animal Disease and Human Health, Sichuan Agricultural University, Ya’an 625014, China
| |
Collapse
|
10
|
Simultaneous detection of antibodies against Apx toxins ApxI, ApxII, ApxIII, and ApxIV in pigs with known and unknown Actinobacillus pleuropneumoniae exposure using a multiplexing liquid array platform. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 21:85-95. [PMID: 24226091 DOI: 10.1128/cvi.00451-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Surveillance for the presence of Actinobacillus pleuropneumoniae infection in a population plays a central role in controlling the disease. In this study, a 4-plex fluorescent microbead-based immunoassay (FMIA), developed for the simultaneous detection of IgG antibodies to repeat-in-toxin (RTX) toxins (ApxI, ApxII, ApxIII, and ApxIV) of A. pleuropneumoniae, was evaluated using (i) blood serum samples from pigs experimentally infected with each of the 15 known A. pleuropneumoniae serovars or with Actinobacillus suis, (ii) blood serum samples from pigs vaccinated with a bacterin containing A. pleuropneumoniae serovar 1, 3, 5, or 7, and (iii) blood serum samples from pigs with an unknown A. pleuropneumoniae exposure status. The results were compared to those obtained in a previous study where a dual-plate complement fixation test (CFT) and three commercially available enzyme-linked immunosorbent assays (ELISAs) were conducted on the same sample set. On samples from experimentally infected pigs, the 4-plex Apx FMIA detected specific seroconversion to Apx toxins as early as 7 days postinfection in a total of 29 pigs inoculated with 14 of the 15 A. pleuropneumoniae serovars. Seroconversion to ApxII and ApxIII was detected by FMIA in pigs inoculated with A. suis. The vaccinated pigs showed poor humoral responses against ApxI, ApxII, ApxIII, and ApxIV. In the field samples, the humoral response to ApxIV and the A. pleuropneumoniae seroprevalence increased with age. This novel FMIA (with a sensitivity of 82.7% and a specificity of 100% for the anti-ApxIV antibody) was found to be more sensitive and accurate than current tests (sensitivities, 9.5 to 56%; specificity, 100%) and is potentially an improved tool for the surveillance of disease and for monitoring vaccination compliance.
Collapse
|
11
|
Rossi CC, de Araújo EF, de Queiroz MV, Bazzolli DMS. Characterization of the omlA gene from different serotypes of Actinobacillus pleuropneumoniae: A new insight into an old approach. Genet Mol Biol 2013; 36:243-51. [PMID: 23885207 PMCID: PMC3715291 DOI: 10.1590/s1415-47572013005000012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 01/29/2013] [Indexed: 11/22/2022] Open
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.
Collapse
Affiliation(s)
- Ciro César Rossi
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | | | | | | |
Collapse
|
12
|
Vanni M, Merenda M, Barigazzi G, Garbarino C, Luppi A, Tognetti R, Intorre L. Antimicrobial resistance of Actinobacillus pleuropneumoniae isolated from swine. Vet Microbiol 2011; 156:172-7. [PMID: 22104584 DOI: 10.1016/j.vetmic.2011.10.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 10/14/2011] [Accepted: 10/17/2011] [Indexed: 10/16/2022]
Abstract
The aim of this retrospective study was to evaluate the antimicrobial resistance rates and the trend in resistance of Actinobacillus pleuropneumoniae isolated from pigs in Italy from 1994 to 2009. A total of 992 A. pleuropneumoniae isolates were tested for their susceptibility to a panel of antimicrobial agents in a disk diffusion method. Resistance to 7 drugs (amoxicillin, amoxicillin/clavulanic acid, ampicillin, cefquinome, cotrimoxazole, penicillin G and tilmicosin) showed a significant increasing trend over the time, while for 2 drugs (gentamycin and marbofloxacin) a significant decrease was observed. Resistance to the remaining 14 antimicrobial agents tested did not change significantly over the study period. Most of the isolates retained high susceptibility to antimicrobials usually effective against A. pleuropneumoniae such as amphenicols, fluoroquinolones and ceftiofur. However, high rates of resistance were observed for potentiated sulfa drugs, tetracyclines and penicillins which are currently recommended antimicrobials for pig pleuropneumonia therapy. Our results suggest the importance of continued monitoring of A. pleuropneumoniae clinical isolates in order to choose the most appropriate treatment of infections and to control the increase of resistance to currently used antimicrobials.
Collapse
Affiliation(s)
- Michele Vanni
- Section of Veterinary Pharmacology & Toxicology, Department of Veterinary Clinics, Faculty of Veterinary Medicine, University of Pisa, Pisa, Italy.
| | | | | | | | | | | | | |
Collapse
|
13
|
Predicting genetic traits and epitope analysis of apxIVA in Actinobacillus pleuropneumoniae. J Microbiol 2011; 49:462-8. [DOI: 10.1007/s12275-011-0449-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Accepted: 01/13/2011] [Indexed: 11/26/2022]
|
14
|
Ohba T, Shibahara T, Kobayashi H, Takashima A, Nagoshi M, Araki M, Takizawa K, Kubo M. Prevalence of granulomatous pleuropneumonia associated with Actinobacillus pleuropneumoniae serotype 2 in slaughter pigs. J Vet Med Sci 2010; 71:1089-92. [PMID: 19721364 DOI: 10.1292/jvms.71.1089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A total of 14,818 slaughtered pigs were examined macroscopically. Of these, 25 pigs with porcine pleuropneumonia were collected and the relations among Actinobacillus spp. and granulomatous lesions in organs (lungs and tonsils) were evaluated. In the lungs, only Actinobacillus pleuropneumoniae serotype 2 was isolated from 20 of the pigs. Histologically, granulomatous pneumonia with A. pleuropneumoniae antigen was detected in 8 of the pigs. The antigen was visible in the centers of the lesions along with asteroid bodies, epithelioid cells and multinucleated giant cells. In the tonsils, granulomatous lesions were not detected, although A. pleuropneumoniae serotype 2 (5 pigs), serotype 7 (1 pig), Actinobacillus porcitonsillarum (1 pig) and Actinobacillus minor (1 pig) were isolated. The present survey suggests that multifocal granulomatous pneumonia in slaughter pigs could be highly associated with A. pleuropneumoniae serotype 2 infection.
Collapse
Affiliation(s)
- Takemi Ohba
- Toyama Prefectural Meat Inspection Center, Imizu, Japan
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Arya G, Niven DF. Production of haemolysins by strains of the Actinobacillus minor/"porcitonsillarum" complex. Vet Microbiol 2009; 141:332-41. [PMID: 19819087 DOI: 10.1016/j.vetmic.2009.09.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 09/18/2009] [Accepted: 09/22/2009] [Indexed: 11/29/2022]
Abstract
Actinobacillus minor and "Actinobacillus porcitonsillarum" are distinguished by their haemolytic activities, the latter organism being haemolytic and the former, non-haemolytic. Analysis of a whole genome shotgun sequence, however, revealed that A. minor strain 202, like "A. porcitonsillarum", possesses a haemolysin-encoding apxII operon. The purpose of this study was therefore to investigate haemolysin production by this organism and also by three additional members of the A. minor/"porcitonsillarum" complex, strains 33PN and 7ATS and A. minor strain NM305(T). Primers based on sequences within the apxII genes of strain 202 allowed the amplification of appropriately sized fragments from DNA from strain 33PN suggesting that this organism also possesses an apxII operon. Analysis of a whole genome shotgun sequence failed to reveal any trace of an apxII operon in strain NM305(T) and attempts to amplify apxII genes from DNA from strain 7ATS also failed. Strains 202 and 33PN, and surprisingly, the type strain of A. minor and strain 7ATS, were all found to be haemolysin-positive as growth media from cultures of these organisms could promote the lysis of erythrocytes in suspension. The erythrocyte specificities of the haemolysins produced by strains 202 and 33PN indicated that the haemolytic activities exhibited by these organisms were due to ApxII. In keeping with the apparent lack of apxII genes in strains NM305(T) and 7ATS, the haemolysins produced by these organisms were not erythrocyte-specific and with both organisms, haemolytic activity appeared to be due to a combination of heat-stable and heat-labile components. The identities of these components, however, remain unknown.
Collapse
Affiliation(s)
- Gitanjali Arya
- Department of Natural Resource Sciences, Macdonald Campus, McGill University, 21111 Lakeshore Road, Ste. Anne de Bellevue, Que., Canada H9X 3V9
| | | |
Collapse
|
16
|
Angen O, Ahrens P, Jessing SG. Development of a multiplex PCR test for identification of Actinobacillus pleuropneumoniae serovars 1, 7, and 12. Vet Microbiol 2008; 132:312-8. [PMID: 18572332 DOI: 10.1016/j.vetmic.2008.05.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Revised: 05/07/2008] [Accepted: 05/09/2008] [Indexed: 11/24/2022]
Abstract
A PCR assay for simultaneous species identification and separation of Actinobacillus pleuropneumoniae serovars 1, 7 and 12 was developed. Primers specific for genes involved in biosynthesis of the capsular polysaccharides (cps genes) of serovars 1, 7, and 12 were combined with a species-specific PCR test based on the omlA gene. The PCR test was evaluated with the serovar reference strains of A. pleuropneumoniae as well as 183 Danish field isolates. For all typable strains, a complete correspondence was found between results obtained with the multiplex PCR test and results from the traditional serotyping methods. Among eight serologically cross-reacting strains designated K1:O7, seven isolates produced amplicons of similar sizes as serovar 1 and one isolate produced amplicons of similar sizes as serovar 7. The species specificity of the assay was evaluated using a collection of 126 strains representing 25 different species within the family Pasteurellaceae including 45 field strains of the phylogenetically affiliated species Actinobacillus lignieresii. All these isolates tested negative for the cps genes by the multiplex PCR test except for 6 isolates of A. lignieresii. Five of these isolates produced an amplicon identical to the cps gene of serovar 7, whereas one isolate produced an amplicon identical to the cps gene of serovar 1. In addition, four isolates of Actinobacillus genomospecies 1 tested positive for the omlA gene but negative for the cps genes. The test represents a convenient and specific method for serotyping A. pleuropneumoniae in diagnostic laboratories.
Collapse
Affiliation(s)
- Oystein Angen
- National Veterinary Institute, Technical University of Denmark, Bülowsvej 27, DK-1790 Copenhagen V, Denmark.
| | | | | |
Collapse
|
17
|
Small multidrug resistance plasmids in Actinobacillus porcitonsillarum. Plasmid 2008; 59:144-52. [PMID: 18190962 DOI: 10.1016/j.plasmid.2007.11.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 10/29/2007] [Accepted: 11/27/2007] [Indexed: 11/21/2022]
Abstract
The complete nucleotide sequences of six Actinobacillus porcitonsillarum plasmids pKMA202 (13.425-kb), pKMA1467 (11.115-kb), pKMA5 (9.549-kb), pIMD50 (8.751-kb), pKMA505 (8.632-kb) and pKMA757 (4.556-kb) and three Actinobacillus pleuropneumoniae plasmids pPSAS1522 (4.244-kb), pARD3079 (3.884-kb) and pKMA2425 (3.156-kb) were determined. All the plasmids contain the sulfonamide resistance gene sul2. One A. pleuropneumoniae plasmid and five A. porcitonsillarum plasmids also have the streptomycin resistance gene strA. Among these latter five A. porcitonsillarum plasmids, four also harbor the beta-lactam resistance gene bla(ROB-1). This study is the first report of multidrug resistance plasmids in the non-pathogenic A. porcitonsillarum.
Collapse
|
18
|
Liu J, Chen X, Lin L, Tan C, Chen Y, Guo Y, Jin M, Guo A, Bei W, Chen H. Potential use an Actinobacillus pleuropneumoniae double mutant strain ΔapxIICΔapxIVA as live vaccine that allows serological differentiation between vaccinated and infected animals. Vaccine 2007; 25:7696-705. [PMID: 17767980 DOI: 10.1016/j.vaccine.2007.07.053] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 07/23/2007] [Accepted: 07/28/2007] [Indexed: 10/23/2022]
Abstract
Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia, a highly contagious and often fatal disease. We have previously reported the construction and characterization of a single gene apxIIC deletion mutant HB04C(-) based on A. pleuropneumoniae serovar 7 which produces ApxII toxin and ApxIV. A precisely defined DeltaapxIICDeltaapxIVA double-deletion mutant of A. pleuropneumoniae was constructed based on HB04C(-) by transconjugation and counterselection, and the levels of virulence of the DeltaapxIIC single mutant and DeltaapxIICDeltaapxIVA double mutant were compared in an experimental infection in mice and pigs. The results demonstrated that the DeltaapxIICDeltaapxIVA double mutant strain was less virulent than HB04C(-). Despite attenuation of virulence, the DeltaapxIICDeltaapxIVA double mutant remains immunogenic and conferred a similar level of protective immunity to pigs against challenge with a lethal dose of a heterologous fully virulent standard serovar 1 strain of A. pleuropneumoniae. The results of the virulence study suggest that ApxIV is a critical virulence factor of A. pleuropneumoniae serovar 7 and is able to induce clinical disease, but it not required for efficient vaccination of pigs against A. pleuropneumoniae infection. Two weeks after the booster immunization, animals vaccinated with HB04C(-) were positive in the ApxIVAM-ELISA based on a recombinant GST-fusion protein GST-ApxIVAM as the solid-phase antigen while animals vaccinated with the DeltaapxIICDeltaapxIVA double mutant were negative. These data demonstrate that the double mutant DeltaapxIICDeltaapxIVA can be used as an effective live marker vaccine allowing serological differentiation between vaccinated and infected animals.
Collapse
Affiliation(s)
- Jinlin Liu
- Laboratory of Animal Infectious Diseases, College of Animal Science & Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Ohba T, Shibahara T, Kobayashi H, Takashima A, Minami Y, Kubo M. Granulomatous Lymphadenitis and Pneumonia Associated with Actinobacillus porcitonsillarum in a Slaughter Pig. J Comp Pathol 2007; 137:82-86. [PMID: 17629969 DOI: 10.1016/j.jcpa.2007.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Accepted: 03/30/2007] [Indexed: 10/23/2022]
Abstract
Multiple coalescing granulomatous foci were detected in the pulmonary hilar and mediastinal lymph nodes and lung of a slaughtered pig aged 6 months. Haemolytic, Gram-negative bacilli were isolated from the lymph nodes. The isolate (strain TO17214) strongly cross-reacted with sera against Actinobacillus pleuropneumoniae serotype 12 in slide agglutination tests. Comparative 16S rDNA gene sequencing analysis identified strain TO17214 as Actinobacillus porcitonsillarum. Histologically, extensive inflammation took the form of large granulomas consisting of epithelioid cells and multinucleated giant cells in the lymph nodes and lung, and Gram-negative bacilli were discernible in the centres of the lesions. Immunohistochemically, the organisms cross-reacted with polyclonal antibodies against A. pleuropneumoniae serotypes 12 and 2. The results indicated that A. porcitonsillarum, previously considered non-pathogenic, can induce multifocal granulomatous lymphadenitis accompanied by pneumonia in the growing-finishing pig.
Collapse
Affiliation(s)
- T Ohba
- Toyama Prefectural Meat Inspection Centre, 28-4 Shinbori, Imizu 934-0035
| | - T Shibahara
- Epidemiological Research Team, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba 305-0856, Japan.
| | - H Kobayashi
- Epidemiological Research Team, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba 305-0856, Japan
| | | | | | - M Kubo
- Epidemiological Research Team, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba 305-0856, Japan
| |
Collapse
|
20
|
Martínez E, Maldonado J. Pulmonary isolation of Actinobacillus porcitonsillarum
in pigs in Europe. Vet Rec 2006; 159:642-3. [PMID: 17088304 DOI: 10.1136/vr.159.19.642-a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
21
|
Rayamajhi N, Shin SJ, Kang SG, Lee DY, Ahn JM, Yoo HS. Development and use of a multiplex polymerase chain reaction assay based on Apx toxin genes for genotyping of Actinobacillus pleuropneumoniae isolates. J Vet Diagn Invest 2006; 17:359-62. [PMID: 16130995 DOI: 10.1177/104063870501700410] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Actinobacillus pleuropneumoniae (A. pleuropneumoniae) is the etiological agent of a porcine pleuropneumonia that threatens the global swine industry. The major pathogenic toxins of A. pleuropneumoniae include ApxI, ApxII, ApxIII, and ApxIV, which are serotype or serovar specific. Several techniques have been developed for the identification and typing of A. pleuropneumoniae. Serological assays are used to identify and serotype A. pleuropneumoniae, but factors such as cross-reactivity limit their specificity. Labor, time, and the requirement for specific antibodies are also drawbacks of these assays. Multistep polymerase chain reaction (PCR) techniques based on apx genes have been reported for the identification and typing of A. pleuropneumoniae. This study developed multiplex PCR for the identification and genotyping of A. pleuropneumoniae based on apx genes. This multiplex PCR technique was successful in differentiating 11 of 15 reference serotypes. Five different primer sets were used to amplify the 4 apx genes from each serotype in a single-step reaction. The multiplex PCR reported in this study was further used in genotyping 51 field isolates of A. pleuropneumoniae from different regions of Korea. The concomitant amplification of all 4 apx genes makes multiplex PCR more specific and convenient for the diagnosis and genotyping of A. pleuropneumoniae.
Collapse
Affiliation(s)
- Nabin Rayamajhi
- Department of Infectious Diseases, College of Veterinary Medicine, School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea
| | | | | | | | | | | |
Collapse
|
22
|
Kuhnert P, Schlatter Y, Frey J. Characterization of the type I secretion system of the RTX toxin ApxII in “Actinobacillus porcitonsillarum”. Vet Microbiol 2005; 107:225-32. [PMID: 15863281 DOI: 10.1016/j.vetmic.2005.01.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 01/28/2005] [Accepted: 01/28/2005] [Indexed: 11/18/2022]
Abstract
Strains of Actinobacillus porcitonsillarum are regularly isolated from the tonsils of healthy pigs. A. porcitonsillarum is non pathogenic but phenotypically it strongly resembles the pathogenic species Actinobacillus pleuropneumoniae, thereby interfering with the diagnosis of the latter. A. porcitonsillarum is hemolytic but unlike A. pleuropneumoniae, it contains only apxII genes and not apxI or apxIII genes. In contrast to the truncated apxII operon of A. pleuropneumoniae, which lacks the type I secretion genes BD, characterization of the apxII operon in A. porcitonsillarum revealed that it contains an intact and complete apxII operon. This shows a typical RTX operon structure with the gene arrangement apxIICABD. The region upstream of the apxII operon is also different from that in A. pleuropneumoniae and contains an additional gene, aspC, encoding a putative aspartate aminotransferase. Trans-complementation experiments in Escherichia coli and A. pleuropneumoniae indicated that the entire apxII operon of A. porcitonsillarum is sufficient to express and secrete the ApxIIA toxin and that the ApxIIA toxin of A. pleuropneumoniae can be secreted by the type I secretion system encoded by apxIIBD. These findings suggest that the complete apxII operon found in A. porcitonsillarum might be an ancestor of the truncated homologue found in A. pleuropneumoniae. The genetic context of the apxII locus in A. porcitonsillarum and A. pleuropneumoniae suggests that in the latter, the contemporary truncated operon is the result of a recombination event within the species, rather than a horizontal transfer of an incomplete operon.
Collapse
Affiliation(s)
- Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Laenggass-Strasse 122, CH-3001 Bern, Switzerland.
| | | | | |
Collapse
|
23
|
Korczak B, Christensen H, Emler S, Frey J, Kuhnert P. Phylogeny of the family Pasteurellaceae based on rpoB sequences. Int J Syst Evol Microbiol 2004; 54:1393-1399. [PMID: 15280320 DOI: 10.1099/ijs.0.03043-0] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sequences of the gene encoding theβ-subunit of the RNA polymerase (rpoB) were used to delineate the phylogeny of the familyPasteurellaceae. A total of 72 strains, including the type strains of the major described species as well as selected field isolates, were included in the study. Selection of universalrpoB-derived primers for the family allowed straightforward amplification and sequencing of a 560 bp fragment of therpoBgene. In parallel, 16S rDNA was sequenced from all strains. The phylogenetic tree obtained with therpoBsequences reflected the major branches of the tree obtained with the 16S rDNA, especially at the genus level. Only a few discrepancies between the trees were observed. In certain cases therpoBphylogeny was in better agreement with DNA–DNA hybridization studies than the phylogeny derived from 16S rDNA. TherpoBgene is strongly conserved within the various species of the family ofPasteurellaceae. Hence,rpoBgene sequence analysis in conjunction with 16S rDNA sequencing is a valuable tool for phylogenetic studies of thePasteurellaceaeand may also prove useful for reorganizing the current taxonomy of this bacterial family.
Collapse
Affiliation(s)
- Bożena Korczak
- Institute of Veterinary Bacteriology, University of Bern, CH-3012 Bern, Switzerland
| | - Henrik Christensen
- Department of Veterinary Microbiology, The Royal Veterinary and Agricultural University, DK-1870 Frederiksberg C, Denmark
| | - Stefan Emler
- SmartGene GmbH, PSE-C EPFL-Ecublens, CH-1015 Lausanne, Switzerland
| | - Joachim Frey
- Institute of Veterinary Bacteriology, University of Bern, CH-3012 Bern, Switzerland
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, University of Bern, CH-3012 Bern, Switzerland
| |
Collapse
|
24
|
Dreyfus A, Schaller A, Nivollet S, Segers RPAM, Kobisch M, Mieli L, Soerensen V, Hüssy D, Miserez R, Zimmermann W, Inderbitzin F, Frey J. Use of recombinant ApxIV in serodiagnosis of Actinobacillus pleuropneumoniae infections, development and prevalidation of the ApxIV ELISA. Vet Microbiol 2004; 99:227-38. [PMID: 15066725 DOI: 10.1016/j.vetmic.2004.01.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2003] [Revised: 11/21/2003] [Accepted: 01/17/2004] [Indexed: 10/26/2022]
Abstract
Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, which causes worldwide severe losses in pig farming. The virulence of the 15 serotypes of A. pleuropneumoniae is mainly determined by the three major RTX toxins ApxI, ApxII and ApxIII, which are secreted by the different serotypes in various combinations. A fourth RTX toxin, ApxIV, is produced by all 15 serotypes only during infection of pigs, but not under in vitro conditions. Pigs infected with A. pleuropneumoniae show specific antibodies directed against ApxIV. In contrast, antibodies against the other three toxins ApxI, ApxII and ApxIII are also found in pigs free of A. pleuropneumoniae. The antibodies to the three latter might result from other, less pathogenic Actinobacillus species such as A. rossii and A. suis. We used a recombinant protein based on the N'-terminal part of ApxIV to serologically detect A. pleuropneumoniae infections in pigs by immunoblot analysis. The analysis of sera of experimentally infected pigs revealed that ApxIV-immunoblots detected A. pleuropneumoniae infections in the second to third week post infection. We developed an indirect ELISA based on the purified recombinant N'-terminal moiety of ApxIV. The analysis of sera from pigs that were experimentally or naturally infected by A. pleuropneumoniae, and of sera of pigs that were free of A. pleuropneumoniae, revealed that the ELISA had a specificity of 100% and a sensitivity of 93.8%. The pre-validation study of the ApxIV-ELISA revealed that the latter was able to detect A. pleuropneumoniae-positive herds, even when clinical and pathological signs of porcine pleuropneumonia were not evident. Pigs vaccinated with a subunit vaccine Porcilis App were serologically negative in the ApxIV-ELISA.
Collapse
Affiliation(s)
- A Dreyfus
- Institute of Veterinary Bacteriology, University of Berne, Laenggass-Strasse 122, CH-3001 Bern, Switzerland
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Christensen H, Bisgaard M. Revised definition of Actinobacillus sensu stricto isolated from animals. A review with special emphasis on diagnosis. Vet Microbiol 2004; 99:13-30. [PMID: 15019108 DOI: 10.1016/j.vetmic.2003.12.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2003] [Accepted: 12/02/2003] [Indexed: 11/16/2022]
Abstract
The taxonomy of the members of the genus Actinobacillus associated with animals has been reviewed with focus on classification and identification including molecular based characterization, typing and identification. Out of the 22 species or species like taxa reported as Actinobacillus, 19 are associated with animals. When classified on the basis of 16S rRNA sequence based phylogenetic analysis, DNA-DNA hybridizations and phenotypic analysis, Actinobacillus sensu stricto is restricted to include A. lignieresii, A. pleuropneumoniae, A. equuli subsp. equuli, A. equuli subsp. haemolyticus (taxon 11 of Bisgaard), A. hominis, A. suis, A. ureae, A. arthritidis (taxon 9 of Bisgaard), Actinobacillus genomospecies 1 and 2 and the taxa 8 and 26 of Bisgaard. The remaining 11 species of Actinobacillus are unrelated to A. sensu stricto and should consequently be grouped with other genera or be renamed as new genera depending on new data. Identification of members of Actinobacillus at species level is possible through phenotypic characterization combined with information on host of isolation. PCR tests are available for specific detection of A. pleuropneumoniae. Only A. pleuropneumoniae is presently considered as a primary pathogen. Based on different types of RTX genes it is possible to PCR type A. pleuropneumoniae to serotype level. PCR might also be used for the specific detection of A. equuli subsp. haemolyticus. Epidemiological investigations and surveillance have so far included serotyping, multilocus enzyme electrophoresis (MLEE), ribotyping and restriction fragment length profiling.
Collapse
Affiliation(s)
- Henrik Christensen
- Department of Veterinary Microbiology, The Royal Veterinary and Agricultural University, Stigbøjlen 4, 1870 Frederiksberg C, Denmark.
| | | |
Collapse
|
26
|
Fittipaldi N, Broes A, Harel J, Kobisch M, Gottschalk M. Evaluation and field validation of PCR tests for detection of Actinobacillus pleuropneumoniae in subclinically infected pigs. J Clin Microbiol 2004; 41:5085-93. [PMID: 14605143 PMCID: PMC262496 DOI: 10.1128/jcm.41.11.5085-5093.2003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Eight PCR tests were evaluated for their abilities to detect Actinobacillus pleuropneumoniae in swine tonsils. At first they were compared regarding their specificities by using A. pleuropneumoniae and related bacterial species and their analytical sensitivities by using tonsils experimentally infected in vitro. PCRs were carried out both directly with tonsil homogenates (direct PCR) and after culture of the sample (after-culture PCR). Most tests demonstrated good specificities; however, some tests gave false-positive results with some non-A. pleuropneumoniae species. High degrees of variation in the analytical sensitivities among the tests were observed for the direct PCRs (10(9) to 10(2) CFU/g of tonsil), whereas those of most of the after-culture PCRs were similar (10(2) CFU/g of tonsil). In a second phase, the effects of sample storage time and storage conditions were evaluated by using tonsils from experimentally infected animals. Storage at -20 degrees C allowed the detection of the organism for at least 4 months. Finally, the omlA PCR test described by Savoye et al. (C. Savoye et al., Vet. Microbiol. 73:337-347, 2000) and the commercially available Adiavet App PCR test were further validated with field samples. Their effectiveness was compared to those of standard and immunomagnetic separation-based methods of bacterial isolation. In addition, a comparison of tonsil biopsy specimens (from living animals) and whole tonsils (collected at the slaughterhouse) was also conducted. A. pleuropneumoniae was neither isolated nor detected by PCR from a herd serologically negative for A. pleuropneumoniae. PCR was more sensitive than the standard isolation method with whole tonsils from three infected herds. After-culture PCR offered the highest degree of sensitivity (93 and 83% for the omlA and Adiavet App PCRs, respectively). The PCR detection rate was higher with whole tonsils than with tonsil biopsy specimens. Good agreement (kappa = 0.65) was found between the presence of A. pleuropneumoniae in tonsils and the individual serological status of the animals.
Collapse
Affiliation(s)
- Nahuel Fittipaldi
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada J2S 7C6
| | | | | | | | | |
Collapse
|