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Erickson VI, Dung TT, Khoi LM, Hounmanou YMG, Phu TM, Dalsgaard A. Genomic Insights into Edwardsiella ictaluri: Molecular Epidemiology and Antimicrobial Resistance in Striped Catfish ( Pangasianodon hypophthalmus) Aquaculture in Vietnam. Microorganisms 2024; 12:1182. [PMID: 38930563 PMCID: PMC11205447 DOI: 10.3390/microorganisms12061182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 05/21/2024] [Accepted: 06/07/2024] [Indexed: 06/28/2024] Open
Abstract
Edwardsiella ictaluri is responsible for causing bacillary necrosis (BNP) in striped catfish (Pangasianodon hypophthalmus) in Vietnam. This study offers a comprehensive genomic characterization of E. ictaluri to enhance understanding of the molecular epidemiology, virulence, and antimicrobial resistance. E. ictaluri isolates were collected from diseased striped catfish in the Mekong Delta. The species was confirmed through PCR. Antimicrobial susceptibility testing was conducted using minimum inhibitory concentrations for commonly used antimicrobials. Thirty representative isolates were selected for whole genome sequencing to delineate their genomic profiles and phylogeny. All strains belonged to ST-26 and exhibited genetic relatedness, differing by a maximum of 90 single nucleotide polymorphisms. Most isolates carried multiple antimicrobial resistance genes, with the tet(A) gene present in 63% and floR in 77% of the genomes. The ESBL gene, blaCTX-M-15, was identified in 30% of the genomes. Three plasmid replicon types were identified: IncA, p0111, and IncQ1. The genomes clustered into two clades based on their virulence gene profile, one group with the T3SS genes and one without. The genetic similarity among Vietnamese isolates suggests that disease spread occurs within the Mekong region, underscoring the importance of source tracking, reservoir identification, and implementation of necessary biosecurity measures to mitigate spread of BNP.
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Affiliation(s)
- Vera Irene Erickson
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark; (V.I.E.); (Y.M.G.H.)
| | - Tu Thanh Dung
- Department of Aquatic Pathology, Can Tho University, Can Tho 94000, Vietnam; (T.T.D.); (L.M.K.)
| | - Le Minh Khoi
- Department of Aquatic Pathology, Can Tho University, Can Tho 94000, Vietnam; (T.T.D.); (L.M.K.)
| | - Yaovi Mahuton Gildas Hounmanou
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark; (V.I.E.); (Y.M.G.H.)
| | - Tran Minh Phu
- Department of Aquatic Product Processing, Can Tho University, Can Tho 94000, Vietnam;
| | - Anders Dalsgaard
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg, Denmark; (V.I.E.); (Y.M.G.H.)
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Janda JM, Duman M. Expanding the Spectrum of Diseases and Disease Associations Caused by Edwardsiella tarda and Related Species. Microorganisms 2024; 12:1031. [PMID: 38792860 PMCID: PMC11124366 DOI: 10.3390/microorganisms12051031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/12/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024] Open
Abstract
The genus Edwardsiella, previously residing in the family Enterobacteriaceae and now a member of the family Hafniaceae, is currently composed of five species, although the taxonomy of this genus is still unsettled. The genus can primarily be divided into two pathogenic groups: E. tarda strains are responsible for almost all human infections, and two other species (E. ictaluri, E. piscicida) cause diseases in fish. Human infections predominate in subtropical habitats of the world and in specific geospatial regions with gastrointestinal disease, bloodborne infections, and wound infections, the most common clinical presentations in decreasing order. Gastroenteritis can present in many different forms and mimic other intestinal disturbances. Chronic gastroenteritis is not uncommon. Septicemia is primarily found in persons with comorbid conditions including malignancies and liver disease. Mortality rates range from 9% to 28%. Most human infections are linked to one of several risk factors associated with freshwater or marine environments such as seafood consumption. In contrast, edwardsiellosis in fish is caused by two other species, in particular E. ictaluri. Both E. ictaluri and E. piscicida can cause massive outbreaks of disease in aquaculture systems worldwide, including enteric septicemia in channel catfish and tilapia. Collectively, these species are increasingly being recognized as important pathogens in clinical and veterinary medicine. This article highlights and provides a current perspective on the taxonomy, microbiology, epidemiology, and pathogenicity of this increasingly important group.
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Affiliation(s)
- J. Michael Janda
- Kern County Public Health Laboratory, Bakersfield, CA 93306, USA
| | - Muhammed Duman
- Aquatic Animal Disease Department, Faculty of Veterinary Medicine, Bursa Uludag University, 16059 Bursa, Turkey;
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Nhinh DT, Giang NTH, Van Van K, Dang LT, Dong HT, Hoai TD. Widespread presence of a highly virulent Edwardsiella ictaluri strain in farmed tilapia, Oreochromis spp. Transbound Emerg Dis 2022; 69:e2276-e2290. [PMID: 35461191 DOI: 10.1111/tbed.14568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 04/12/2022] [Accepted: 04/18/2022] [Indexed: 11/28/2022]
Abstract
Edwardsiella ictaluri is an emerging bacterial pathogen that affects farmed tilapia (Oreochromis spp.). This study reports the widespread presence of E. ictaluri in farmed tilapia in Vietnam. Among 26 disease outbreaks from nine provinces in Northern Vietnam during 2019-2021, 19 outbreaks originated from imported seeds, while outbreaks in seven farms were from domestic sources. Clinically sick fish showed the appearance of numerous white spots in visceral organs, and accumulative mortality reached 30%-65%. A total of 26 representative bacterial isolates recovered from 26 disease outbreaks were identified as E. ictaluri based on a combination of phenotypic tests, genus- and species-specific polymerase chain reaction assays, 16S rRNA and gyrB sequencing, and phylogenetic analysis. All isolates harbored the same virulence gene profiles esrC+ , evpC+ , ureA-C+ , eseI- , escD- , and virD4- . Antimicrobial susceptibility tests revealed that 80.8%-100% of isolates were multidrug resistant, with resistance to 4-8 antimicrobials in the groups of penicillin, macrolides, sulfonamides, amphenicols, and glycopeptides. The experimental challenge successfully induced disease that mimicked natural infection. The median lethal doses (LD50 ) of the tested isolates (n = 4) were 42-61 colony forming units/fish, indicating their extremely high virulence. This emerging pathogen is established and has spread to various geographical locations, causing serious impacts on farmed tilapia in northern Vietnam. It is likely that this pathogen will continue to spread through contaminated stocks (both imported and domestic sources) and persist. Thus, increased awareness, combined with biosecurity measures and emergent vaccination programs is essential to mitigate the negative impact of this emerging disease on the tilapia farming industry. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Doan Thi Nhinh
- Faculty of Fisheries, Vietnam National University of Agriculture, Hanoi, 131004, Vietnam.,Research Institute for Aquaculture No 1, Bac Ninh, 16352, Vietnam
| | - Nguyen Thi Huong Giang
- Faculty of Veterinary Medicine, Vietnam National University of Agriculture, Hanoi, 131004, Vietnam
| | - Kim Van Van
- Faculty of Fisheries, Vietnam National University of Agriculture, Hanoi, 131004, Vietnam
| | - Lua Thi Dang
- Research Institute for Aquaculture No 1, Bac Ninh, 16352, Vietnam
| | - Ha Thanh Dong
- AARM, Department of Food, Agriculture and Bioresources, School of Environment, Resources & Development (SERD), Asian Institute of Technology (AIT), Klong Luang, Pathumthani, Thailand
| | - Truong Dinh Hoai
- Faculty of Fisheries, Vietnam National University of Agriculture, Hanoi, 131004, Vietnam
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Machimbirike VI, Pornputtapong N, Senapin S, Wangkahart E, Srisapoome P, Khunrae P, Rattanarojpong T. A multi-epitope chimeric protein elicited a strong antibody response and partial protection against Edwardsiella ictaluri in Nile tilapia. JOURNAL OF FISH DISEASES 2022; 45:1-18. [PMID: 34472110 DOI: 10.1111/jfd.13525] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 07/26/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Edwardsiella ictaluri infects several fish species and protection of the all the susceptible fish hosts from the pathogen using a monovalent vaccine is impossible because the species is composed of host-based genotypes that are genetic, serological and antigenic heterogenous. Here, immunoinformatic approach was employed to design a cross-immunogenic chimeric EiCh protein containing multi-epitopes. The chimeric EiCh protein is composed of 11 B-cell epitopes and 7 major histocompatibility complex class II epitopes identified from E. ictaluri immunogenic proteins previously reported. The 49.32 kDa recombinant EiCh protein was expressed in vitro in Escherichia coli BL-21 (DE3) after which inclusion bodies were successfully solubilized and refolded. Ab initio protein modelling revealed secondary and tertiary structures. Secondary structure was confirmed by circular dichroism spectroscopy. Antigenicity of the chimeric EiCh protein was exhibited by strong reactivity with serum from striped catfish and Nile tilapia experimentally infected with E. ictaluri. Furthermore, immunogenicity of the chimeric EiCh protein was investigated in vivo in Nile tilapia juveniles and it was found that the protein could strongly induce production of specific antibodies conferring agglutination activity and partially protected Nile tilapia juveniles with a relative survival percentage (RPS) of 42%. This study explored immunoinformatics as reverse vaccinology approach in vaccine design for aquaculture to manage E. ictaluri infections.
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Affiliation(s)
- Vimbai Irene Machimbirike
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok, Thailand
| | - Natapol Pornputtapong
- Department of Biochemistry and Microbiology, Faculty of Medicine, Faculty of Pharmaceutical Sciences and Center of Excellence in Systems Biology, Chulalongkorn University, Bangkok, Thailand
| | - Saengchan Senapin
- Fish Health Platform, Faculty of Science, Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Mahidol University, Bangkok, Thailand
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani, Thailand
| | - Eakapol Wangkahart
- Division of Fisheries, Department of Agricultural Technology, Faculty of Technology, Mahasarakham University, Maha Sarakham, Thailand
| | - Prapansak Srisapoome
- Laboratory of Aquatic Animal Health Management, Department of Aquaculture, Faculty of Fisheries, Kasetsart University, Bangkok, Thailand
| | - Pongsak Khunrae
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok, Thailand
| | - Triwit Rattanarojpong
- Department of Microbiology, Faculty of Science, King Mongkut's University of Technology Thonburi (KMUTT), Bangkok, Thailand
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Nguyen TT, Xuan TTT, Ngoc TH, Duyen LTM, Vinh TQ, My PDT, Hoang HA, Nga LP. Diverse Bacteriophages Infecting the Bacterial Striped Catfish Pathogen Edwardsiella ictaluri. Microorganisms 2021; 9:microorganisms9091830. [PMID: 34576725 PMCID: PMC8465730 DOI: 10.3390/microorganisms9091830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 08/17/2021] [Accepted: 08/25/2021] [Indexed: 11/16/2022] Open
Abstract
Bacteriophages infecting Edwardsiella ictaluri have been less investigated, although the host bacterium is one of the most important fish pathogens causing enteric septicemia of catfish (ESC). We present here two distinctly novel bacteriophages vB_EiM_PVN06 and vB_EiA_PVN09 infecting Edwardsiella ictaluri E1, with their geographical origins from the Mekong Delta, Vietnam. Bacteriophage vB_EiM_PVN06 native to a mud sample reveals complete differences of biological properties with the phage vB_EiA_PVN09 originated from a viscus of a healthy catfish (Pangasianodon hypophthalmus) cultured in the same area. Morphological analyses combined with genomic data indicate that phage vB_EiM_PVN06 is classified to Myoviridae family and shares high similarity with E. ictaluri phage PEi21 genome, while vB_EiA_PVN09 is a member of Teseptimavirus genus, Autographiviridae family, and mostly closes to phage vB_EcoP_IME390. The vB_EiA_PVN09 is a T7-like bacteriophage, which has been firstly found infecting to E. ictaluri, and host range analysis also evidences for the cross-infection of this phage to Escherichia coli K12 and Escherichia coli DH5α. Together, our research highlights the diversity of bacteriophages infecting the pathogen E. ictaluri and suggests further explorations of lytic phages in environmental niches, to be exploited in feasible strategies of phage therapy in ESC disease control.
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Affiliation(s)
- Tan-Trung Nguyen
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - Tran T. T. Xuan
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - To H. Ngoc
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - Le T. My Duyen
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - Tu Q. Vinh
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - Pham D. T. My
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - Hoang A. Hoang
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
| | - Le P. Nga
- Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet, District 10, Ho Chi Minh City 700000, Vietnam; (T.-T.N.); (T.T.T.X.); (T.H.N.); (L.T.M.D.); (T.Q.V.); (P.D.T.M.); (H.A.H.)
- Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City 700000, Vietnam
- Correspondence: ; Tel.: +84-902-966166
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Comparative genomics of Edwardsiellaictaluri revealed four distinct host-specific genotypes and thirteen potential vaccine candidates. Genomics 2021; 113:1976-1987. [PMID: 33848586 DOI: 10.1016/j.ygeno.2021.04.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 12/31/2020] [Accepted: 04/05/2021] [Indexed: 02/02/2023]
Abstract
Edwardsiella ictaluri has been considered an important threat for catfish aquaculture industry for more than 4 decades and an emerging pathogen of farmed tilapia but only 9 sequenced genomes were publicly available. We hereby report two new complete genomes of E. ictaluri originated from diseased hybrid red tilapia (Oreochromis sp.) and striped catfish (Pangasianodon hypophthalmus) in Southeast Asia. E. ictaluri species has an open pan-genome consisting of 2615 core genes and 5592 pan genes. Phylogenetic analysis using core genome MLST (cgMLST) and ANI values consistently placed E. ictaluri isolates into 4 host-specific genotypes. Presence of unique genes and absence of certain genes from each genotype provided potential biomarkers for further development of genotyping scheme. Vaccine candidates with high antigenic, solubility and secretion probabilities were identified in silico from the core genes. Microevolution within the species is brought about by bacteriophages and insertion elements and possibly drive host adaptation.
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Tekedar HC, Blom J, Kalindamar S, Nho S, Karsi A, Lawrence ML. Comparative genomics of the fish pathogens Edwardsiella ictaluri 93-146 and Edwardsiella piscicida C07-087. Microb Genom 2020; 6. [PMID: 32108566 PMCID: PMC7067208 DOI: 10.1099/mgen.0.000322] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Edwardsiella ictaluri and Edwardsiella piscicida are important fish pathogens affecting cultured and wild fish worldwide. To investigate the genome-level differences and similarities between catfish-adapted strains in these two species, the complete E. ictaluri 93-146 and E. piscicida C07-087 genomes were evaluated by applying comparative genomics analysis. All available complete (10) and non-complete (19) genomes from five Edwardsiella species were also included in a systematic analysis. Average nucleotide identity and core-genome phylogenetic tree analyses indicated that the five Edwardsiella species were separated from each other. Pan-/core-genome analyses for the 29 strains from the five species showed that genus Edwardsiella members have 9474 genes in their pan genome, while the core genome consists of 1421 genes. Orthology cluster analysis showed that E. ictaluri and E. piscicida genomes have the greatest number of shared clusters. However, E. ictaluri and E. piscicida also have unique features; for example, the E. ictaluri genome encodes urease enzymes and cytochrome o ubiquinol oxidase subunits, whereas E. piscicida genomes encode tetrathionate reductase operons, capsular polysaccharide synthesis enzymes and vibrioferrin-related genes. Additionally, we report for what is believed to be the first time that E. ictaluri 93-146 and three other E. ictaluri genomes encode a type IV secretion system (T4SS), whereas none of the E. piscicida genomes encode this system. Additionally, the E. piscicida C07-087 genome encodes two different type VI secretion systems. E. ictaluri genomes tend to encode more insertion elements, phage regions and genomic islands than E. piscicida. We speculate that the T4SS could contribute to the increased number of mobilome elements in E. ictaluri compared to E. piscicida. Two of the E. piscicida genomes encode full CRISPR-Cas regions, whereas none of the E. ictaluri genomes encode Cas proteins. Overall, comparison of the E. ictaluri and E. piscicida genomes reveals unique features and provides new insights on pathogenicity that may reflect the host adaptation of the two species.
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Affiliation(s)
- Hasan C Tekedar
- College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus-Liebig-University Giessen, 35392 Giessen, Hesse, Germany
| | - Safak Kalindamar
- College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Seongwon Nho
- Division of Microbiology, National Center for Toxicological Research/FDA, Jefferson, AR, USA
| | - Attila Karsi
- College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
| | - Mark L Lawrence
- College of Veterinary Medicine, Mississippi State University, Mississippi State, MS, USA
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Kayansamruaj P, Areechon N, Unajak S. Development of fish vaccine in Southeast Asia: A challenge for the sustainability of SE Asia aquaculture. FISH & SHELLFISH IMMUNOLOGY 2020; 103:73-87. [PMID: 32335313 DOI: 10.1016/j.fsi.2020.04.031] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 02/23/2020] [Accepted: 04/15/2020] [Indexed: 05/08/2023]
Abstract
Southeast (SE) Asia plays an important role in global food security as this region has been regarded as one of the major producers of aquaculture product and, to date, freshwater fish accounted for one-third of the total aquaculture in SE Asia. The intensification of freshwater farming corresponding to increase of consumer demands has inevitably led to the emergence and re-emergence of diseases causing tremendous economic loss in the region. Nile tilapia (Oreochromis niloticus) and striped catfish (Pangasianodon hypophthalmus), the major freshwater fish species of SE Asia, have been reported susceptible to several bacterial pathogens, e.g. Streptococcus agalactiae, Edwardsiella ictalurid and Flavobacterium columnare. Since only a limited number of vaccines being registered and marketed, these pathogenic organisms still represent a severe threat to aquaculture industry in SE Asia. However, there is profound advancement in the understanding of disease epidemiology, pathogenic mechanisms, teleost mucosal immunity and vaccine delivery system over the last few years. This review aimed to summarize those recent findings which hopefully can provide novel insight into the future development of suitable vaccine and vaccination regime against bacterial infection in SE Asia region.
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Affiliation(s)
- Pattanapon Kayansamruaj
- Department of Aquaculture, Faculty of Fisheries, Kasetsart University, 10900, Chatuchak, Bangkok, Thailand.
| | - Nontawith Areechon
- Department of Aquaculture, Faculty of Fisheries, Kasetsart University, 10900, Chatuchak, Bangkok, Thailand
| | - Sasimanas Unajak
- Department of Biochemistry, Faculty of Science, Kasetsart University, 10900, Chatuchak, Bangkok, Thailand.
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Griffin MJ, Petty BD, Ware C, Fogelson SB. Recovery and confirmation of Edwardsiella piscicida from a black crappie Pomoxis nigromaculatus (Lesueur, 1829). JOURNAL OF FISH DISEASES 2019; 42:1457-1461. [PMID: 31309579 DOI: 10.1111/jfd.13056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/03/2019] [Accepted: 05/07/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Matt J Griffin
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, Mississippi
| | - B Denise Petty
- North Florida Aquatic Veterinary Services, Fort White, Florida
| | - Cynthia Ware
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, Mississippi
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Hoang HA, Yen MH, Ngoan VT, Nga LP, Oanh DTH. Virulent bacteriophage of Edwardsiella ictaluri isolated from kidney and liver of striped catfish Pangasianodon hypophthalmus in Vietnam. DISEASES OF AQUATIC ORGANISMS 2018; 132:49-56. [PMID: 30530930 DOI: 10.3354/dao03302] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Striped catfish Pangasianodon hypophthalmus farmed in the Mekong Delta, Vietnam, represents an important contribution to Vietnamese aquaculture exports. However, these fish are affected by frequent disease outbreaks across the entire region. One of the most common infections involves white spots in the internal organs, caused by the bacterium Edwardsiella ictaluri. In this study, a virulent phage specific to E. ictaluri, designated MK7, was isolated from striped catfish kidney and liver samples and characterized. Morphological analysis indicates probable placement in the family Myoviridae with a 65 nm icosahedral head and a 147 %%CONV_ERR%% 19 nm tail. A double-stranded DNA genome of approximately 34 kb was predicted by restriction fragment analysis following digestion with SmaI. The adsorption affinity (ka) of the MK7 phage was estimated as 1.6 %%CONV_ERR%% 10-8 ml CFU-1 min-1, and according to a 1-step growth curve, its latent period and burst size were ~45 min and ~55 phage particles per infected host cell, respectively. Of the 17 bacterial strains tested, MK7 only infected E. ictaluri, although other species of Edwardsiella were not tested. E. ictaluri was also challenged in vitro, in both broth and water from a striped catfish pond and was inactivated by MK7 for 15 h in broth and 51 h in pond water. Thus, initial characterization of phage MK7 indicates its potential utility as a biotherapeutic agent against E. ictaluri infection in striped catfish. This is the first report of a lytic phage specific to an important striped catfish pathogen.
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Affiliation(s)
- Hoang A Hoang
- Department of Biotechnology, Faculty of Chemical Engineering, Ho Chi Minh City University of Technology, Vietnam National University - Ho Chi Minh City (VNU-HCM), 268 Ly Thuong Kiet St., District 10, HCMC, Vietnam
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Kelly E, Martin PAJ, Gibson-Kueh S, Morgan DL, Ebner BC, Donaldson J, Buller N, Crook DA, Brooks S, Davis AM, Hammer MP, Foyle L, Hair S, Lymbery AJ. First detection of Edwardsiella ictaluri (Proteobacteria: Enterobacteriaceae) in wild Australian catfish. JOURNAL OF FISH DISEASES 2018; 41:199-208. [PMID: 28836666 DOI: 10.1111/jfd.12696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 06/07/2023]
Abstract
The bacterium Edwardsiella ictaluri is considered to be one of the most significant pathogens of farmed catfish in the United States of America and has also caused mortalities in farmed and wild fishes in many other parts of the world. E. ictaluri is not believed to be present in wild fish populations in Australia, although it has previously been detected in imported ornamental fishes held in quarantine facilities. In an attempt to confirm freedom from the bacterium in Australian native fishes, we undertook a risk-based survey of wild catfishes from 15 sites across northern Australia. E. ictaluri was detected by selective culturing, followed by DNA testing, in Wet Tropics tandan (Tandanus tropicanus) from the Tully River, at a prevalence of 0.40 (95% CI 0.21-0.61). The bacterium was not found in fishes sampled from any of the other 14 sites. This is the first report of E. ictaluri in wild fishes in Australia.
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Affiliation(s)
- E Kelly
- Freshwater Fish Group & Fish Health Unit, Centre for Fish & Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
| | - P A J Martin
- Freshwater Fish Group & Fish Health Unit, Centre for Fish & Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
| | - S Gibson-Kueh
- Freshwater Fish Group & Fish Health Unit, Centre for Fish & Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
| | - D L Morgan
- Freshwater Fish Group & Fish Health Unit, Centre for Fish & Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
| | - B C Ebner
- Freshwater Fish Group & Fish Health Unit, Centre for Fish & Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
- TropWATER, James Cook University, Townsville, Qld, Australia
- CSIRO Land & Water, Atherton, Qld, Australia
| | - J Donaldson
- TropWATER, James Cook University, Townsville, Qld, Australia
- CSIRO Land & Water, Atherton, Qld, Australia
| | - N Buller
- Animal Health Laboratories, Department of Agriculture and Food of Western Australia, South Perth, WA, Australia
| | - D A Crook
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Casuarina, NT, Australia
| | - S Brooks
- Queensland Department of Agriculture and Fisheries, Brisbane, Qld, Australia
| | - A M Davis
- TropWATER, James Cook University, Townsville, Qld, Australia
- CSIRO Land & Water, Atherton, Qld, Australia
| | - M P Hammer
- Museum and Art Gallery of the Northern Territory, Darwin, NT, Australia
| | - L Foyle
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Qld, Australia
| | - S Hair
- Animal Health Laboratories, Department of Agriculture and Food of Western Australia, South Perth, WA, Australia
| | - A J Lymbery
- Freshwater Fish Group & Fish Health Unit, Centre for Fish & Fisheries Research, School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia
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12
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Phillips ACN, Reichley SR, Ware C, Griffin MJ. Edwardsiella ictaluri infection in Pangasius catfish imported from West Bengal into the Southern Caribbean. JOURNAL OF FISH DISEASES 2017; 40:743-756. [PMID: 27592704 DOI: 10.1111/jfd.12552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 07/14/2016] [Accepted: 07/18/2016] [Indexed: 06/06/2023]
Abstract
In response to a mortality event, seven Pangasius catfish (Pangasianodon hypophthalmus) were submitted to the University of the West Indies, School of Veterinary Medicine, Trinidad and Tobago, for diagnostic evaluation. These fish were part of a consignment that arrived from Kolkata two weeks earlier. Fish presented with perianal haemorrhage and blister-like swellings on the skin which ruptured to leave ulcers. Edwardsiella ictaluri was consistently recovered from the brain and skin. Repetitive sequence-mediated PCR analysis revealed genetic fingerprints consistent with E. ictaluri isolates from farm-raised channel catfish in Mississippi, USA. Plasmid analysis of the case isolates identified two unique plasmids that differ slightly in conformation and content from the pEI1 and pEI2 plasmids described for E. ictaluri from other fish hosts. The case isolates were also PCR negative for several E. ictaluri virulence factors. The biological implications of these genetic differences are unclear and warrant further study. This is the first report and documentation of E. ictaluri infection in Trinidad and Tobago, suggesting the pathogen may have been introduced concurrently with the importation of fish. This report emphasizes the importance of adequate health screenings of imported lots to minimize the threat of introducing E. ictaluri to non-endemic areas.
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Affiliation(s)
- A C N Phillips
- Department of Clinical Veterinary Sciences, Faculty of Medical Sciences, School of Veterinary Medicine, The University of the West Indies, St. Augustine, Trinidad and Tobago
| | - S R Reichley
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS, USA
| | - C Ware
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS, USA
| | - M J Griffin
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Stoneville, MS, USA
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13
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Nhung NT, Cuong NV, Thwaites G, Carrique-Mas J. Antimicrobial Usage and Antimicrobial Resistance in Animal Production in Southeast Asia: A Review. Antibiotics (Basel) 2016; 5:E37. [PMID: 27827853 PMCID: PMC5187518 DOI: 10.3390/antibiotics5040037] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/19/2016] [Accepted: 10/20/2016] [Indexed: 12/25/2022] Open
Abstract
Southeast Asia is an area of great economic dynamism. In recent years, it has experienced a rapid rise in the levels of animal product production and consumption. The region is considered to be a hotspot for infectious diseases and antimicrobial resistance (AMR). We reviewed English-language peer-reviewed publications related to antimicrobial usage (AMU) and AMR in animal production, as well as antimicrobial residues in meat and fish from 2000 to 2016, in the region. There is a paucity of data from most countries and for most bacterial pathogens. Most of the published work relates to non-typhoidal Salmonella (NTS), Escherichia coli (E. coli), and Campylobacter spp. (mainly from Vietnam and Thailand), Enterococcus spp. (Malaysia), and methicillin-resistant Staphylococcus aureus (MRSA) (Thailand). However, most studies used the disk diffusion method for antimicrobial susceptibility testing; breakpoints were interpreted using Clinical Standard Laboratory Institute (CSLI) guidelines. Statistical models integrating data from publications on AMR in NTS and E. coli studies show a higher overall prevalence of AMR in pig isolates, and an increase in levels of AMR over the years. AMU studies (mostly from Vietnam) indicate very high usage levels of most types of antimicrobials, including beta-lactams, aminoglycosides, macrolides, and quinolones. This review summarizes information about genetic determinants of resistance, most of which are transferrable (mostly plasmids and integrons). The data in this review provide a benchmark to help focus research and policies on AMU and AMR in the region.
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Affiliation(s)
- Nguyen T Nhung
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.
| | - Nguyen V Cuong
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.
| | - Guy Thwaites
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Old Road Campus, Roosevelt Drive, Oxford OX3 7BN, UK.
| | - Juan Carrique-Mas
- Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.
- Centre for Tropical Medicine, Nuffield Department of Clinical Medicine, Oxford University, Old Road Campus, Roosevelt Drive, Oxford OX3 7BN, UK.
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14
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Nhu TQ, Park SB, Kim SW, Lee JS, Im SP, Lazarte JMS, Seo JP, Lee WJ, Kim JS, Jung TS. Matrix-assisted laser desorption ionization-time of flight mass spectrometry based identification of Edwardsiella ictaluri isolated from Vietnamese striped catfish (Pangasius hypothalamus). J Vet Sci 2016; 17:377-83. [PMID: 26726022 PMCID: PMC5037306 DOI: 10.4142/jvs.2016.17.3.377] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 09/24/2015] [Accepted: 11/09/2015] [Indexed: 11/20/2022] Open
Abstract
Edwardsiella (E.) ictaluri is a major bacterial pathogen that affects commercially farmed striped catfish (Pangasius hypothalamus) in Vietnam. In a previous study, 19 strains of E. ictaluri collected from striped catfish were biochemically identified with an API-20E system. Here, the same 19 strains were used to assess the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS; applied using a MALDI Biotyper) to conduct rapid, easy and accurate identification of E. ictaluri. MALDI-TOF MS could directly detect the specific peptide patterns of cultured E. ictaluri colonies with high (> 2.0, indicating species-level identification) scores. MALDI Biotyper 3.0 software revealed that all of the strains examined in this study possessed highly similar peptide peak patterns. In addition, electrophoresis (SDS-PAGE) and subsequent immuno-blotting using a specific chicken antibody (IgY) against E. ictaluri revealed that the isolates had highly similar protein profiles and antigenic banding profiles. The results of this study suggest that E. ictaluri isolated from striped catfish in Vietnam have homologous protein compositions. This is important, because it indicates that MALDI-TOF MS analysis could potentially outperform the conventional methods of identifying E. ictaluri.
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Affiliation(s)
- Truong Quynh Nhu
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Seong Bin Park
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Si Won Kim
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Jung Seok Lee
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Se Pyeong Im
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Jassy Mary S Lazarte
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | | | | | - Jae Sung Kim
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Tae Sung Jung
- Laboratory of Aquatic Animal Diseases, Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
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15
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Griffin MJ, Reichley SR, Greenway TE, Quiniou SM, Ware C, Gao DX, Gaunt PS, Yanong RPE, Pouder DB, Hawke JP, Soto E. Comparison of Edwardsiella ictaluri isolates from different hosts and geographic origins. JOURNAL OF FISH DISEASES 2016; 39:947-69. [PMID: 26661707 DOI: 10.1111/jfd.12431] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 10/04/2015] [Accepted: 10/05/2015] [Indexed: 05/04/2023]
Abstract
The intraspecific variability of E. ictaluri isolates from different origins was investigated. Isolates were recovered from farm-raised catfish (Ictalurus punctatus) in Mississippi, USA, tilapia (Oreochromis niloticus) cultured in the Western Hemisphere and zebrafish (Danio rerio) propagated in Florida, USA. These isolates were phenotypically homologous and antimicrobial profiles were largely similar. Genetically, isolates possessed differences that could be exploited by repetitive-sequence-mediated PCR and gyrB sequence, which identified three distinct E. ictaluri genotypes: one associated with catfish, one from tilapia and a third from zebrafish. Plasmid profiles were also group specific and correlated with rep-PCR and gyrB sequences. The catfish isolates possessed profiles typical of those described for E. ictaluri isolates; however, plasmids from the zebrafish and tilapia isolates differed in both composition and arrangement. Furthermore, some zebrafish and tilapia isolates were PCR negative for several E. ictaluri virulence factors. Isolates were serologically heterogenous, as serum from a channel catfish exposed to a catfish isolate had reduced antibody activity to tilapia and zebrafish isolates. This work identifies three genetically distinct strains of E. ictaluri from different origins using rep-PCR, 16S, gyrB and plasmid sequencing, in addition to antimicrobial and serological profiling.
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Affiliation(s)
- M J Griffin
- Thad Cochran National Warmwater Aquaculture Center, Mississippi State University, Stoneville, MS, USA
| | - S R Reichley
- Thad Cochran National Warmwater Aquaculture Center, Mississippi State University, Stoneville, MS, USA
| | - T E Greenway
- Thad Cochran National Warmwater Aquaculture Center, Mississippi State University, Stoneville, MS, USA
| | - S M Quiniou
- Thad Cochran National Warmwater Aquaculture Center, Warmwater Aquaculture Research Unit, Agricultural Research Service, United States Department of Agriculture, Stoneville, MS, USA
| | - C Ware
- Thad Cochran National Warmwater Aquaculture Center, Mississippi State University, Stoneville, MS, USA
| | - D X Gao
- Thad Cochran National Warmwater Aquaculture Center, Mississippi State University, Stoneville, MS, USA
| | - P S Gaunt
- Thad Cochran National Warmwater Aquaculture Center, Mississippi State University, Stoneville, MS, USA
| | - R P E Yanong
- Tropical Aquaculture Laboratory, Fisheries and Aquatic Sciences Program, School of Forest Resources and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Ruskin, FL, USA
| | - D B Pouder
- Tropical Aquaculture Laboratory, Fisheries and Aquatic Sciences Program, School of Forest Resources and Conservation, Institute of Food and Agricultural Sciences, University of Florida, Ruskin, FL, USA
| | - J P Hawke
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, USA
| | - E Soto
- Department of Biomedical Sciences, School of Veterinary Medicine, Ross University, Basseterre, St. Kitts, West Indies
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16
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Genome modifications and cloning using a conjugally transferable recombineering system. ACTA ACUST UNITED AC 2015; 8:24-35. [PMID: 28352570 PMCID: PMC4980705 DOI: 10.1016/j.btre.2015.08.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 08/24/2015] [Accepted: 08/24/2015] [Indexed: 11/21/2022]
Abstract
The genetic modification of primary bacterial disease isolates is challenging due to the lack of highly efficient genetic tools. Herein we describe the development of a modified PCR-based, λ Red-mediated recombineering system for efficient deletion of genes in Gram-negative bacteria. A series of conjugally transferrable plasmids were constructed by cloning an oriT sequence and different antibiotic resistance genes into recombinogenic plasmid pKD46. Using this system we deleted ten different genes from the genomes of Edwardsiella ictaluri and Aeromonas hydrophila. A temperature sensitive and conjugally transferable flp recombinase plasmid was developed to generate markerless gene deletion mutants. We also developed an efficient cloning system to capture larger bacterial genetic elements and clone them into a conjugally transferrable plasmid for facile transferring to Gram-negative bacteria. This system should be applicable in diverse Gram-negative bacteria to modify and complement genomic elements in bacteria that cannot be manipulated using available genetic tools.
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17
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Wise DJ, Greenway TE, Byars TS, Griffin MJ, Khoo LH. Oral Vaccination of Channel Catfish against Enteric Septicemia of Catfish Using a Live Attenuated Edwardsiella ictaluri Isolate. JOURNAL OF AQUATIC ANIMAL HEALTH 2015; 27:135-143. [PMID: 26030354 DOI: 10.1080/08997659.2015.1032440] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Enteric septicemia of catfish (ESC), caused by Edwardsiella ictaluri, is the most problematic bacterial disease affecting catfish aquaculture in the southeastern United States. Efforts to develop an effective ESC vaccine have had limited industrial success. In commercial settings, ESC vaccines are typically administered by immersion when fry are transferred from the hatchery to rearing ponds. While this approach is a practical method of mass delivery, this strategy administers vaccines to very young fish, which lack a fully developed immune system. To circumvent this limitation, an oral vaccination strategy was evaluated as a means of immunizing catfish at the fingerling stage of production, when fish possess a more complete immune arsenal. A virulent E. ictaluri isolate (S97-773) was attenuated by successive passage on media containing increasing concentrations of rifamycin. In laboratory trials, cultured vaccine was diluted and mixed with feed (100 mL diluted vaccine/454 g feed). This mixture was then fed to Channel Catfish Ictalurus punctatus fingerlings. Two separate dilutions of cultured vaccine (1:10 and 1:100) were used to create the vaccine-feed mixture, equating to estimated doses of 5 × 10⁷ and 5 × 10⁶ CFU/g of feed, respectively. After 30 d, catfish were exposed by immersion (1 × 10⁶ CFU/mL) to the virulent parental strain of E. ictaluri. The target dose (1:100 dilution, ∼5 × 10⁶ CFU/g of feed) offered exceptional protection (relative percent survival = 82.6-100%). In addition, negligible deaths occurred in fish vaccinated at 10 times the target dose (1:10 dilution, ∼5 × 10⁷ CFU/g of feed). In pond trials, antibody production increased 18-fold in orally vaccinated fish. When compared with nonvaccinated controls, vaccination significantly improved survival, feed fed, feed conversion, biomass produced, and total harvest. This research demonstrates Channel Catfish can be successfully immunized in a commercial setting against E. ictaluri with a single dose of an orally delivered, live attenuated, E. ictaluri vaccine.
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Affiliation(s)
- David J Wise
- a Thad Cochran National Warmwater Aquaculture Center, Mississippi Agricultural and Forestry Experiment Station , Mississippi State University , Post Office Box 197, Stoneville , Mississippi 38776 , USA
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