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Valenzuela-Aviles P, Torrealba D, Figueroa C, Mercado L, Dixon B, Conejeros P, Gallardo-Matus J. Why vaccines fail against Piscirickettsiosis in farmed salmon and trout and how to avoid it: A review. Front Immunol 2022; 13:1019404. [PMID: 36466828 PMCID: PMC9714679 DOI: 10.3389/fimmu.2022.1019404] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 10/24/2022] [Indexed: 09/28/2023] Open
Abstract
Piscirickettsiosis is the most severe, persistent, and damaging disease that has affected the Chilean salmon industry since its origins in the 1980s. As a preventive strategy for this disease, different vaccines have been developed and used over the last 30 years. However, vaccinated salmon and trout frequently die in the sea cages and the use of antibiotics is still high demonstrating the low efficiency of the available vaccines. The reasons why the vaccines fail so often are still debated, but it could involve different extrinsic and intrinsic factors. Among the extrinsic factors, mainly associated with chronic stress, we can distinguish: 1) biotic including coinfection with sea lice, sealions attacks or harmful algal blooms; 2) abiotic including low oxygen or high temperature; and 3) farm-management factors including overcrowding or chemical delousing treatments. Among the intrinsic factors, we can distinguish: 1) fish-related factors including host's genetic variability (species, population and individual), sex or age; 2) pathogen-related factors including their variability and ability to evade host immune responses; and 3) vaccine-related factors including low immunogenicity and poor matches with the circulating pathogen strain. Based on the available evidence, in order to improve the development and the efficacy of vaccines against P. salmonis we recommend: a) Do not perform efficacy evaluations by intraperitoneal injection of pathogens because they generate an artificial protective immune response, instead cohabitation or immersion challenges must be used; b) Evaluate the diversity of pathogen strains in the field and ensure a good antigenic match with the vaccines; c) Investigate whether host genetic diversity could be improved, e.g. through selection, in favor of better and longer responses to vaccination; d) To reduce the stressful effects at the cage level, controlling the co-infection of pathogens and avoiding fish overcrowding. To date, we do not know the immunological mechanisms by which the vaccines against P. salmonis may or may not generate protection. More studies are required to identify what type of response, cellular or molecular, is required to develop effective vaccines.
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Affiliation(s)
- Paula Valenzuela-Aviles
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Débora Torrealba
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Carolina Figueroa
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Luis Mercado
- Grupo de Marcadores Inmunológicos en Organismos Acuáticos, Pontificia Universidad Católica de Valparaíso, Instituto de Biología, Valparaíso, Chile
| | - Brian Dixon
- Department of Biology, Faculty of Science, University of Waterloo, Waterloo, Canada
| | - Pablo Conejeros
- Centro de Investigación y Gestión de Recursos Naturales (CIGREN), Facultad de Ciencias, Instituto de Biología, Universidad de Valparaíso, Valparaíso, Chile
| | - José Gallardo-Matus
- Laboratorio de Genética y Genómica Aplicada, Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
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2
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Isla A, Saldarriaga-Córdoba M, Fuentes DE, Albornoz R, Haussmann D, Mancilla-Schulz J, Martínez A, Figueroa J, Avendaño-Herrera R, Yáñez A. Multilocus sequence typing detects new Piscirickettsia salmonis hybrid genogroup in Chilean fish farms: Evidence for genetic diversity and population structure. JOURNAL OF FISH DISEASES 2019; 42:721-737. [PMID: 30851000 DOI: 10.1111/jfd.12976] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 01/15/2019] [Accepted: 01/18/2019] [Indexed: 06/09/2023]
Abstract
Piscirickettsia salmonisis the causative bacterial pathogen of piscirickettsiosis, a salmonid disease that causes notable mortalities in the worldwide aquaculture industry. Published research describes the phenotypic traits, virulence factors, pathogenicity and antibiotic-resistance potential for various P. salmonisstrains. However, evolutionary and genetic information is scarce for P. salmonis. The present study used multilocus sequence typing (MLST) to gain insight into the population structure and evolution of P. salmonis. Forty-two Chilean P. salmonisisolates, as well as the type strain LF-89T , were recovered from diseased Salmo salar, Oncorhynchus kisutchand Oncorhynchus mykissfrom two Chilean Regions. MLST assessed the loci sequences of dnaK, efp, fumC, glyA, murG, rpoD and trpB. Bioinformatics analyses established the genetic diversity among P. salmonis isolates (H = 0.5810). A total of 23 sequence types (ST) were identified, 53.48% of which were represented by ST1, ST5 and ST2. Population structure analysis through polymorphism patterns showed few polymorphic sites (218 nucleotides from 4,010 bp), while dN/dS ratio analysis indicated purifying selection for dnaK, epf, fumC, murG, and rpoD but neutral selection for the trpB loci. The standardized index of association indicated strong linkage disequilibrium, suggesting clonal population structure. However, recombination events were detected in a group of seven isolates. Findings included genogroups homologous to the LF-89T and EM-90 strains, as well as a seven-isolate hybrid genogroup recovered from both assessed regions (three O. mykiss and four S. salar isolates). The presented MLST scheme has comparative potential, with promising applications in studying distinct P. salmonis isolates (e.g., from different hosts, farms, geographical areas) and in understanding the epidemiology of this pathogen.
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Affiliation(s)
- Adolfo Isla
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
| | - Mónica Saldarriaga-Córdoba
- Centro de Investigación en Recursos Naturales y Sustentabilidad, Universidad Bernardo O'Higgins, Santiago, Chile
| | - Derie E Fuentes
- Fraunhofer Chile Research Foundation, Center for Systems Biotechnology, Santiago, Chile
| | - Romina Albornoz
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
| | - Denise Haussmann
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Valdivia, Chile
| | | | | | - Jaime Figueroa
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
| | - Ruben Avendaño-Herrera
- Centro de Investigación en Recursos Naturales y Sustentabilidad, Universidad Bernardo O'Higgins, Santiago, Chile
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Viña del Mar, Chile
- Centro de Investigación Marina Quintay (CIMARQ), Universidad Andrés Bello, Quintay, Chile
| | - Alejandro Yáñez
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Andrés Bello, Viña del Mar, Chile
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3
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Millar AD, Tapia P, Gómez FA, Marshall SH, Fuentes DE, Valdes JH. Draft genomes and reference transcriptomes extend the coding potential of the fish pathogen Piscirickettsia salmonis. ELECTRON J BIOTECHN 2018. [DOI: 10.1016/j.ejbt.2018.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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4
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Mancilla M, Saavedra J, Grandón M, Tapia E, Navas E, Grothusen H, Bustos P. The mutagenesis of a type IV secretion system locus of Piscirickettsia salmonis leads to the attenuation of the pathogen in Atlantic salmon, Salmo salar. JOURNAL OF FISH DISEASES 2018; 41:625-634. [PMID: 29251345 DOI: 10.1111/jfd.12762] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 11/06/2017] [Accepted: 11/10/2017] [Indexed: 06/07/2023]
Abstract
Piscirickettsiosis is a threatening infectious disease for the salmon industry, due to it being responsible for significant economic losses. The control of outbreaks also poses considerable environmental challenges. Despite Piscirickettsia salmonis having been discovered as the aetiological agent of the disease more than 25 years ago, its pathogenicity remains poorly understood. Among virulence factors identified so far, type four secretion systems (T4SS) seem to play a key role during the infection caused by the bacterium. We report here the genetic manipulation of P. salmonis by means of the transference of plasmid DNA in mating assays. An insertion cassette was engineered for targeting the icmB gene, which encodes a putative T4SS-ATPase and is carried by one of the chromosomal T4SS clusters found within the genome of P. salmonis PM15972A1, a virulent representative of the EM-90-like strain. The molecular characterization of the resulting mutant strain demonstrated that the insertion interrupted the target gene. Further in vitro testing of the icmB mutant showed a dramatic drop in infectivity as tested in CHSE-214 cells, which is in agreement with its attenuated behaviour observed in vivo. Altogether, our results demonstrate that, similar to other facultative intracellular pathogens, P. salmonis' virulence relies on an intact T4SS.
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Affiliation(s)
- M Mancilla
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
| | - J Saavedra
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
| | - M Grandón
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
| | - E Tapia
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
| | - E Navas
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
| | - H Grothusen
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
| | - P Bustos
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile, Puerto Montt, Chile
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5
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Marshall SH, Flores-Herrera P, Henríquez FA, Gómez FA. Identification and characterization of two variants of the Hfq-sRNA-chaperone in the fish pathogen Piscirickettsia salmonis. JOURNAL OF FISH DISEASES 2018; 41:501-509. [PMID: 29159897 DOI: 10.1111/jfd.12752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/02/2017] [Indexed: 06/07/2023]
Abstract
Small RNA and chaperone proteins form synergistic duos that play pivotal roles in controlling gene expression in bacteria. This is the case for Hfq, a highly pleiotropic pretranslational modulator of general protein expression, which responds to harsh environmental conditions and influences fitness and virulence in a wide range of pathogenic Enterobacteria. Given this relevancy, we evaluated the presence and potential role of Hfq in the fish pathogen Piscirickettsia salmonis, a Gram-negative bacterium that threatens the sustainability of Chilean salmon production. Using bioinformatics tools were identified and characterized two variants of Hfq, which share the consensus RNA-binding domains and the active sites described functional Hfq other bacteria. Additionally, we demonstrated that hfq-1 and hfq-2 were transcriptionally active when growing in cell-free media and in infected susceptible fish cell line. Expression of both genes differed under different growth conditions and under stress, suggesting that their roles might be independent and different, depending on the bacterial physiological status. In conclusion, we demonstrate the existence of two different and functional ORF coding for the hfq marker in marine bacteria and a preliminary analysis indicating that these two novel proteins might have relevant roles in the biology and pathogenic potential of P. salmonis.
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Affiliation(s)
- S H Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - P Flores-Herrera
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - F A Henríquez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - F A Gómez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
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6
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Cortés M, Sánchez P, Ruiz P, Haro R, Sáez J, Sánchez F, Hernández M, Oliver C, Yáñez AJ. In vitro expression of Sec-dependent pathway and type 4B secretion system in Piscirickettsia salmonis. Microb Pathog 2017; 110:586-593. [PMID: 28789875 DOI: 10.1016/j.micpath.2017.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 06/18/2017] [Accepted: 08/04/2017] [Indexed: 11/18/2022]
Abstract
Piscirickettsia salmonis is an intracellular bacterium and the causative agent of Piscirickettsiosis, a disease responsible for considerable mortalities in the Chilean salmon farming industry. Currently, P. salmonis protein translocation across the membrane and the mechanisms by which virulence factors are delivered to host cells are poorly understood. However, it is known that Gram-negative bacteria possess several mechanisms that transport proteins to the periplasmic and extracellular compartments. The aim of this study was to evaluate the expressional changes of several genes in the P. salmonis Sec-dependent pathway and type 4B secretion system during in vitro infection. Genes homologous and the main proteins belonging to Sec-dependent pathway and Type 4 Dot/Icm secretion system were found in the genome and proteome of P. salmonis AUSTRAL-005 strain. Additionally, several genes of these protein transport mechanisms were overexpressed during in vitro P. salmonis infection in SHK-1 cell line. The obtained data indicate that the Sec-dependent pathway and Type 4B secretion system are biologically active during P. salmonis infection. These mechanisms could contribute to the recycling of proteins into the inner and outer bacterial membrane and in translocate virulence factors to infected cell, which would favor the structural integrity and virulence of this bacterium.
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Affiliation(s)
- Marcos Cortés
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4070007 Concepción, Chile
| | - Patricio Sánchez
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4070007 Concepción, Chile
| | - Pamela Ruiz
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4070007 Concepción, Chile
| | - Ronie Haro
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Austral-OMICS, Universidad Austral de Chile, 5110566 Valdivia, Chile
| | - Jerson Sáez
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile
| | - Fabián Sánchez
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4070007 Concepción, Chile
| | - Mauricio Hernández
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Austral-OMICS, Universidad Austral de Chile, 5110566 Valdivia, Chile
| | - Cristian Oliver
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Universidad Andrés Bello, Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias Biológicas, Viña del Mar, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4070007 Concepción, Chile.
| | - Alejandro J Yáñez
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, 5110566 Valdivia, Chile; Austral-OMICS, Universidad Austral de Chile, 5110566 Valdivia, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), 4070007 Concepción, Chile.
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7
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Carril GP, Gómez FA, Marshall SH. Expression of flagellin and key regulatory flagellar genes in the non-motile bacterium Piscirickettsia salmonis. DISEASES OF AQUATIC ORGANISMS 2017; 123:29-43. [PMID: 28177291 DOI: 10.3354/dao03079] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The Piscirickettsia salmonis genome was screened to evaluate potential flagella-related open reading frames, as well as their genomic organization and eventual expression. A complete and organized set of flagellar genes was found for P. salmonis, although no structural flagellum has ever been reported for this bacterium. To gain further understanding, the hierarchical flagellar cascade described for Legionella pneumophila was used as a reference model for putative analysis in P. salmonis. Specifically, 5 of the most relevant genes from this cascade were chosen, including 3 regulatory genes (fleQ, triggers the cascade; fliA, regulates the σ28-coding gene; and rpoN, an RNA polymerase-dependent gene) and 2 terminal structural genes (flaA and flaB, flagellin and a flagellin-like protein, respectively). Kinetic experiments evaluated gene expressions over time, with P. salmonis assessed in 2 liquid, cell-free media and during infection of the SHK-1 fish cell line. Under all conditions, the 5 target genes were primarily expressed during early growth/infection and were differentially expressed when bacteria encountered environmental stress (i.e. a high-salt concentration). Intriguingly, the flagellin monomer was fully expressed under all growth conditions and was located near the bacterial membrane. While no structural flagellum was detected under any condition, the recombinant flagellin monomer induced a proinflammatory response in SHK-1 cells, suggesting a possible immunomodulatory function. The potential implications of these observations are discussed in the context of P. salmonis biology and pathogenic potential.
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Affiliation(s)
- Gabriela P Carril
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso 2340000, Chile
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8
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Bayliss SC, Verner-Jeffreys DW, Bartie KL, Aanensen DM, Sheppard SK, Adams A, Feil EJ. The Promise of Whole Genome Pathogen Sequencing for the Molecular Epidemiology of Emerging Aquaculture Pathogens. Front Microbiol 2017; 8:121. [PMID: 28217117 PMCID: PMC5290457 DOI: 10.3389/fmicb.2017.00121] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/17/2017] [Indexed: 01/23/2023] Open
Abstract
Aquaculture is the fastest growing food-producing sector, and the sustainability of this industry is critical both for global food security and economic welfare. The management of infectious disease represents a key challenge. Here, we discuss the opportunities afforded by whole genome sequencing of bacterial and viral pathogens of aquaculture to mitigate disease emergence and spread. We outline, by way of comparison, how sequencing technology is transforming the molecular epidemiology of pathogens of public health importance, emphasizing the importance of community-oriented databases and analysis tools.
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Affiliation(s)
- Sion C Bayliss
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath Bath, UK
| | | | - Kerry L Bartie
- Institute of Aquaculture, University of Stirling Stirling, UK
| | - David M Aanensen
- Department of Infectious Disease Epidemiology, School of Public Health, Imperial College LondonLondon, UK; The Centre for Genomic Pathogen Surveillance, Wellcome Genome CampusCambridge, UK
| | - Samuel K Sheppard
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath Bath, UK
| | - Alexandra Adams
- Institute of Aquaculture, University of Stirling Stirling, UK
| | - Edward J Feil
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath Bath, UK
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9
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Morrison RN, Young ND, Knowles G, Cornish MC, Carson J. Isolation of Tasmanian Rickettsia-like organism (RLO) from farmed salmonids: identification of multiple serotypes and confirmation of pathogenicity. DISEASES OF AQUATIC ORGANISMS 2016; 122:85-103. [PMID: 28000601 DOI: 10.3354/dao03057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Atlantic salmon Salmo salar L. farmed in south-east Tasmania, Australia, are susceptible to infection by the Tasmanian Rickettsia-like organism (TRLO), a Gram-negative bacterium. Here, we report the first isolation of TRLO from south-east Tasmania in pure culture and show that the bacterium is culturable on both specialised enriched agar and in cell culture using the CHSE-214 cell line. In vitro cultured TRLO was used to reproducibly elicit disease in Atlantic salmon parr held in fresh water. In inoculated fish, TRLO was observed intracytoplasmically in peripheral blood leucocytes, suggesting that these cells are responsible for haematogenous dispersal of the bacterium within the host. Fish with experimentally induced disease presented with gross and histopathological changes similar to TRLO-infected fish at commercial marine farms. TRLO was also isolated in culture from farmed Atlantic salmon in the Tamar River and Macquarie Harbour production areas in Tasmania, both of which have no history of TRLO-associated disease. These TRLO isolates appear to be serologically distinct from each other as well as from isolates obtained from south-east Tasmania, linking each serotype to a specific geographical location within Tasmania. Despite the lack of clinical evidence of TRLO-linked disease in fish grown in the Tamar River and Macquarie Harbour, experimental infection trials demonstrably showed the pathogenic potential of these TRLO serovars. Together, these data provide evidence that TRLO is a fastidious, facultative intracellular bacterium and confirm TRLO as a pathogen of Atlantic salmon, causing a disease designated Tasmanian salmonid rickettsiosis.
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Affiliation(s)
- R N Morrison
- Animal Health Laboratories, Department of Primary Industries, Parks, Water and Environment (DPIPWE), Launceston, Tasmania 7250, Australia
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Maisey K, Montero R, Christodoulides M. Vaccines for piscirickettsiosis (salmonid rickettsial septicaemia, SRS): the Chile perspective. Expert Rev Vaccines 2016; 16:215-228. [DOI: 10.1080/14760584.2017.1244483] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Kevin Maisey
- Laboratorio de Inmunología Comparativa, Centro de Biotecnología Acuícola (CBA), Universidad de Santiago de Chile, Santiago, Chile
| | - Ruth Montero
- Laboratorio de Inmunología Comparativa, Centro de Biotecnología Acuícola (CBA), Universidad de Santiago de Chile, Santiago, Chile
| | - Myron Christodoulides
- Neisseria Research, Molecular Microbiology, Academic Unit of Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, University of Southampton Faculty of Medicine, Southampton, UK
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11
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Draft Genome Sequence of a New Zealand Rickettsia-Like Organism Isolated from Farmed Chinook Salmon. GENOME ANNOUNCEMENTS 2016; 4:4/3/e00503-16. [PMID: 27365345 PMCID: PMC4929508 DOI: 10.1128/genomea.00503-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report here the draft genome sequence of a rickettsia-like organism, isolated from a New Zealand Chinook salmon farm experiencing high mortality. The genome is approximately 3 Mb in size, has a G+C content of approximately 39.2%, and is predicted to contain 2,870 coding sequences.
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12
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Sandoval R, Oliver C, Valdivia S, Valenzuela K, Haro RE, Sánchez P, Olavarría VH, Valenzuela P, Avendaño-Herrera R, Romero A, Cárcamo JG, Figueroa JE, Yáñez AJ. Resistance-nodulation-division efflux pump acrAB is modulated by florfenicol and contributes to drug resistance in the fish pathogenPiscirickettsia salmonis. FEMS Microbiol Lett 2016; 363:fnw102. [DOI: 10.1093/femsle/fnw102] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2016] [Indexed: 12/20/2022] Open
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13
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Labra Á, Arredondo-Zelada O, Flores-Herrera P, Marshall SH, Gómez FA. In sílico identification and characterization of putative Dot/Icm secreted virulence effectors in the fish pathogen Piscirickettsia salmonis. Microb Pathog 2015; 92:11-18. [PMID: 26706346 DOI: 10.1016/j.micpath.2015.12.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/26/2015] [Accepted: 12/01/2015] [Indexed: 11/25/2022]
Abstract
Piscirickettsia salmonis seriously affects the Chilean salmon industry. The bacterium is phylogenetically related to Legionella pneumophila and Coxiella burnetii, sharing a Dot/Icm secretion system with them. Although it is well documented that L. pneumophila and C. burnetii secrete different virulence effectors via this Dot/Icm system in order to attenuate host cell responses, to date there have been no reported virulence effectors secreted by the Dot/Icm system of P. salmonis. Using several annotations of P. salmonis genome, here we report an in silico analyses of 4 putative Dot/Icm effectors. Three of them contain ankyrin repeat domains and the typical conserved 3D structures of this protein family. The fourth one is highly similar to one of the Dot/Icm-dependent effectors of L. pneumophila. Additionally, all the potential P. salmonis effectors contain a classical Dot/Icm secretion signal in their C-terminus, consisting of: an E-Block, a hydrophobic residue in -3 or -4 and an electronegative charge. Finally, qPCR analysis demonstrated that these proteins are overexpressed early in infection, perhaps contributing to the generation of a replicative vacuole, a key step in the neutralizing strategy proposed for the Dot/Icm system. In summary, this report identifies four Dot/Icm-dependent effectors in P. salmonis.
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Affiliation(s)
- Álvaro Labra
- Laboratorio de Patógenos Acuícolas, Núcleo de Biotecnología Curauma, Pontificia Universidad Católica de Valparaíso, Chile; Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Curauma, Valparaíso, Chile.
| | - Oscar Arredondo-Zelada
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Curauma, Valparaíso, Chile.
| | - Patricio Flores-Herrera
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Curauma, Valparaíso, Chile.
| | - Sergio H Marshall
- Laboratorio de Patógenos Acuícolas, Núcleo de Biotecnología Curauma, Pontificia Universidad Católica de Valparaíso, Chile; Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Curauma, Valparaíso, Chile; Fraunhofer Chile Research Foundation, Center for Systems Biotechnology, Santiago, Chile.
| | - Fernando A Gómez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330, Curauma, Valparaíso, Chile.
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Henríquez P, Bohle H, Bustamante F, Bustos P, Mancilla M. Polymorphism in gyrA is associated to quinolones resistance in Chilean Piscirickettsia salmonis field isolates. JOURNAL OF FISH DISEASES 2015; 38:415-8. [PMID: 24917068 DOI: 10.1111/jfd.12255] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Revised: 04/07/2014] [Accepted: 04/14/2014] [Indexed: 05/12/2023]
Affiliation(s)
- P Henríquez
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile Ltda, Puerto Montt, Chile
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15
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Comparative Genome Analysis of Two Isolates of the Fish Pathogen Piscirickettsia salmonis from Different Hosts Reveals Major Differences in Virulence-Associated Secretion Systems. GENOME ANNOUNCEMENTS 2014; 2:2/6/e01219-14. [PMID: 25523762 PMCID: PMC4271152 DOI: 10.1128/genomea.01219-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Outbreaks caused by Piscirickettsia salmonis are one of the major threats to the sustainability of the Chilean salmon industry. We report here the annotated draft genomes of two P. salmonis isolates recovered from different salmonid species. A comparative analysis showed that the number of virulence-associated secretion systems constitutes a main genomic difference.
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