1
|
Godoy M, Coca Y, Suárez R, Montes de Oca M, Bledsoe JW, Burbulis I, Caro D, Pontigo JP, Maracaja-Coutinho V, Arias-Carrasco R, Rodríguez-Córdova L, Sáez-Navarrete C. Salmo salar Skin and Gill Microbiome during Piscirickettsia salmonis Infection. Animals (Basel) 2023; 14:97. [PMID: 38200828 PMCID: PMC10778177 DOI: 10.3390/ani14010097] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/13/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
Maintaining the high overall health of farmed animals is a central tenant of their well-being and care. Intense animal crowding in aquaculture promotes animal morbidity especially in the absence of straightforward methods for monitoring their health. Here, we used bacterial 16S ribosomal RNA gene sequencing to measure bacterial population dynamics during P. salmonis infection. We observed a complex bacterial community consisting of a previously undescribed core pathobiome. Notably, we detected Aliivibrio wodanis and Tenacibaculum dicentrarchi on the skin ulcers of salmon infected with P. salmonis, while Vibrio spp. were enriched on infected gills. The prevalence of these co-occurring networks indicated that coinfection with other pathogens may enhance P. salmonis pathogenicity.
Collapse
Affiliation(s)
- Marcos Godoy
- Centro de Investigaciones Biológicas Aplicadas (CIBA), Lago Panguipulli 1390, Puerto Montt 5480000, Región de Los Lagos, Chile; (M.M.d.O.); (D.C.)
- Laboratorio de Biotecnología, Facultad de Ciencias de la Naturaleza, Escuela de Medicina Veterinaria, Universidad San Sebastián, Sede Patagonia, Lago Panguipulli 1390, Puerto Montt 5480000, Región de Los Lagos, Chile
| | - Yoandy Coca
- Doctorado en Ciencias de la Ingeniería, Departamento de Ingeniería Química y Bioprocesos, Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago 7820436, Macul, Chile;
| | - Rudy Suárez
- Programa de Magíster en Acuicultura, Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo 1780000, Elqui, Chile;
| | - Marco Montes de Oca
- Centro de Investigaciones Biológicas Aplicadas (CIBA), Lago Panguipulli 1390, Puerto Montt 5480000, Región de Los Lagos, Chile; (M.M.d.O.); (D.C.)
| | - Jacob W. Bledsoe
- Department of Animal, Veterinary, and Food Sciences, Aquaculture Research Institute, University of Idaho, Hagerman, ID 83332, USA;
| | - Ian Burbulis
- Facultad de Medicina y Ciencia, Centro de Investigación Biomédica, Universidad San Sebastián, Sede Patagonia, Lago Panguipulli 1390, Puerto Montt 5480000, Región de Los Lagos, Chile;
| | - Diego Caro
- Centro de Investigaciones Biológicas Aplicadas (CIBA), Lago Panguipulli 1390, Puerto Montt 5480000, Región de Los Lagos, Chile; (M.M.d.O.); (D.C.)
| | - Juan Pablo Pontigo
- Laboratorio Institucional, Facultad de Ciencias de la Naturaleza, Escuela de Medicina Veterinaria, Universidad San Sebastián, Sede Patagonia, Lago Panguipulli 1390, Puerto Montt 5480000, Región de Los Lagos, Chile;
| | - Vinicius Maracaja-Coutinho
- Unidad de Genómica Avanzada, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 7820436, Macul, Chile;
- Centro de Modelamiento Molecular, Biofísica y Bioinformática (CM2B2), Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 7820436, Macul, Chile
- Beagle Bioinformatics, Santiago 7820436, Macul, Chile
| | - Raúl Arias-Carrasco
- Programa Institucional de Fomento a la Investigación, Desarrollo e Innovación (PIDi), Universidad Tecnológica Metropolitana, Santiago 7820436, Macul, Chile;
| | | | - César Sáez-Navarrete
- Departamento de Ingeniería Química y Bioprocesos, Escuela de Ingeniería, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 7820436, Macul, Chile;
- Centro de Investigación en Nanotecnología y Materiales Avanzados (CIEN-UC), Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago 7820436, Macul, Chile
| |
Collapse
|
2
|
Zrnčić S, Vendramin N, Boutrup TS, Boye M, Madsen L, Nonneman B, Brnić D, Oraić D. First description and diagnostics of disease caused by Piscirickettsia salmonis in farmed European sea bass (Dicentrarchus labrax Linnaeus) from Croatia. JOURNAL OF FISH DISEASES 2021; 44:1033-1042. [PMID: 33754342 DOI: 10.1111/jfd.13366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
During the winter of 2013 and 2016, several Croatian fish farms experienced mortalities in the fry of European sea bass, Dicentrarchus labrax. Affected fish showed abnormal swimming behaviour and reduced appetite, and death ensued several days after the onset of clinical signs of disease. Necropsy revealed pale liver, empty digestive tract, distended gall bladder, and hyperaemia and congestion of the meninges. Routine bacteriological examination tested negative, and virological examination ruled out nodavirus infection. Histological examination revealed multifocal necrosis and extensive inflammation in the brain with abundant cellular debris in the ventricles. Inflammatory cells displayed intra-cytoplasmic basophilic vacuoles leading to suspicion of Piscirickettsia salmonis infection. Fluorescent in situ hybridization using an oligonucleotide probe targeting Domain Bacterium applied to tissue sections tested positive. The pathogen was identified by 16S rRNA gene sequencing of brain material, and the sequence showed 99% similarity with P. salmonis. This result enabled the design of an oligonucleotide probe specifically targeting P. salmonis. In 2016, P. salmonis was successfully isolated on CHAB from the brain of an affected specimen and identified using 16S rRNA gene sequencing and MALDI-TOF. This study describes the first outbreak of disease caused by P. salmonis in sea bass in Croatia, while new diagnostic tools will enable further research on its epidemiology and pathogenicity.
Collapse
Affiliation(s)
| | - Niccolò Vendramin
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, DTU AQUA, Kgs Lyngby, Denmark
| | | | - Mette Boye
- Norwegian Veterinary Institute, Oslo, Norway
| | - Lone Madsen
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, DTU AQUA, Kgs Lyngby, Denmark
| | - Bettina Nonneman
- Unit for Fish and Shellfish Diseases, National Institute of Aquatic Resources, DTU AQUA, Kgs Lyngby, Denmark
| | | | | |
Collapse
|
3
|
Quintanilla JC, González MP, García JP, Olmos P, Contreras-Lynch S. Horizontal transmission of Piscirickettsia salmonis from the wild sub-Antarctic notothenioid fish Eleginops maclovinus to rainbow trout (Oncorhynchus mykiss) under experimental conditions. JOURNAL OF FISH DISEASES 2021; 44:993-1004. [PMID: 33675091 DOI: 10.1111/jfd.13360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 06/12/2023]
Abstract
Piscirickettsia salmonis is the aetiological agent of piscirickettsiosis, a bacterial disease that affects farmed salmonids, causing high mortalities and significant economic losses in the Chilean salmon farm industry. Given the Chilean native fish species Patagonian blenny, Eleginops maclovinus, lives in the vicinity of salmon farms, it is relevant to clarify the epidemiological role that this species could play in the transmission and/or dissemination of this pathogen. This study aimed to evaluate the bidirectional transmission of P. salmonis between the Patagonian blenny and Oncorhynchus mykiss (rainbow trout), via a cohabitation challenge model. The results of this study demonstrated the transmission of the bacteria from Patagonian blennies to rainbow trout, considering the specific mortality in cohabitant rainbow trout, reaching 46%: the necropsy of these specimens, evidencing the characteristic pathological lesions of the disease and the positive results of the qPCR analysis for P. salmonis, in the same individuals. In contrast, no mortalities of Patagonian blenny specimens were recorded in the challenged experimental groups. This study is the first report showing the horizontal transmission of P. salmonis from a native non-salmonid species, such as the Patagonian blenny, to a salmonid species, generating the disease and specific mortality in rainbow trout, using a cohabitation challenge.
Collapse
Affiliation(s)
- Juan Carlos Quintanilla
- Departamento de Salud Hidrobiológica, División de Investigación en Acuicultura, Instituto de Fomento Pesquero, Puerto Montt, Chile
| | - Margarita P González
- Departamento de Salud Hidrobiológica, División de Investigación en Acuicultura, Instituto de Fomento Pesquero, Puerto Montt, Chile
| | - Juan Pablo García
- Departamento de Salud Hidrobiológica, División de Investigación en Acuicultura, Instituto de Fomento Pesquero, Puerto Montt, Chile
| | - Paola Olmos
- Departamento de Salud Hidrobiológica, División de Investigación en Acuicultura, Instituto de Fomento Pesquero, Puerto Montt, Chile
| | - Sergio Contreras-Lynch
- Departamento de Salud Hidrobiológica, División de Investigación en Acuicultura, Instituto de Fomento Pesquero, Puerto Montt, Chile
- Doctorado en Acuicultura, Programa Cooperativo Universidad de Chile, Universidad Católica del Norte, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| |
Collapse
|
4
|
Isla A, Martinez-Hernandez JE, Levipan HA, Haussmann D, Figueroa J, Rauch MC, Maracaja-Coutinho V, Yañez A. Development of a Multiplex PCR Assay for Genotyping the Fish Pathogen Piscirickettsia salmonis Through Comparative Genomics. Front Microbiol 2021; 12:673216. [PMID: 34177855 PMCID: PMC8226252 DOI: 10.3389/fmicb.2021.673216] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/17/2021] [Indexed: 11/20/2022] Open
Abstract
Piscirickettsia salmonis is a bacterial pathogen that severely impact the aquaculture in several countries as Canada, Scotland, Ireland, Norway, and Chile. It provokes Piscirickettsiosis outbreaks in the marine phase of salmonid farming, resulting in economic losses. The monophyletic genogroup LF-89 and a divergent genogroup EM-90 are responsible for the most severe Piscirickettsiosis outbreaks in Chile. Therefore, the development of methods for quick genotyping of P. salmonis genogroups in field samples is vital for veterinary diagnoses and understanding the population structure of this pathogen. The present study reports the development of a multiplex PCR for genotyping LF-89 and EM-90 genogroups based on comparative genomics of 73 fully sequenced P. salmonis genomes. The results revealed 2,322 sequences shared between 35 LF-89 genomes, 2,280 sequences in the core-genome of 38 EM-90 genomes, and 331 and 534 accessory coding sequences each genogroup, respectively. A total of 1,801 clusters of coding sequences were shared among all tested genomes of P. salmonis (LF-89 and EM-90), with 253 and 291 unique sequences for LF-89 and EM-90 genogroups, respectively. The Multiplex-1 prototype was chosen for reliable genotyping because of differences in annealing temperatures and respective reaction efficiencies. This method also identified the pathogen in field samples infected with LF-89 or EM-90 strains, which is not possible with other methods currently available. Finally, the genome-based multiplex PCR protocol presented in this study is a rapid and affordable alternative to classical sequencing of PCR products and analyzing the length of restriction fragment polymorphisms.
Collapse
Affiliation(s)
- Adolfo Isla
- Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Interdisciplinary Center for Aquaculture Research (INCAR), University of Concepcion, Concepción, Chile.,Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Santiago, Chile
| | - J Eduardo Martinez-Hernandez
- Centro de Modelamiento Molecular, Biofísica y Bioinformática - CM2B2, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.,Programa de Doctorado en Genómica Integrativa, Vicerrectoría de Investigación, Universidad Mayor, Santiago, Chile.,Laboratorio de Biología de Redes, Centro de Genómica y Bioinformática, Facultad de Ciencias, Universidad Mayor, Santiago, Chile
| | - Héctor A Levipan
- Laboratorio de Ecopatología y Nanobiomateriales, Departamento de Biología, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaiso, Chile
| | - Denise Haussmann
- Departamento de Ciencias Básicas, Facultad de Ciencias, Universidad Santo Tomás, Santiago, Chile
| | - Jaime Figueroa
- Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Interdisciplinary Center for Aquaculture Research (INCAR), University of Concepcion, Concepción, Chile
| | - Maria Cecilia Rauch
- Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
| | - Vinicius Maracaja-Coutinho
- Centro de Modelamiento Molecular, Biofísica y Bioinformática - CM2B2, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile.,Instituto Vandique, João Pessoa, Brazil.,Beagle Bioinformatics, Santiago, Chile
| | - Alejandro Yañez
- Interdisciplinary Center for Aquaculture Research (INCAR), University of Concepcion, Concepción, Chile.,Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| |
Collapse
|
5
|
Pontigo JP, Espinoza C, Hernandez M, Nourdin G, Oliver C, Avendaño-Herrera R, Figueroa J, Rauch C, Troncoso JM, Vargas-Chacoff L, Yáñez AJ. Protein-Based Vaccine Protect Against Piscirickettsia salmonis in Atlantic Salmon ( Salmo salar). Front Immunol 2021; 12:602689. [PMID: 33679740 PMCID: PMC7927424 DOI: 10.3389/fimmu.2021.602689] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 01/22/2021] [Indexed: 11/25/2022] Open
Abstract
An effective and economical vaccine against the Piscirickettsia salmonis pathogen is needed for sustainable salmon farming and to reduce disease-related economic losses. Consequently, the aquaculture industry urgently needs to investigate efficient prophylactic measures. Three protein-based vaccine prototypes against Piscirickettsia salmonis were prepared from a highly pathogenic Chilean isolate. Only one vaccine effectively protected Atlantic salmon (Salmo salar), in correlation with the induction of Piscirickettsia-specific IgM antibodies and a high induction of transcripts encoding pro-inflammatory cytokines (i.e., Il-1β and TNF-α). In addition, we studied the proteome fraction protein of P. salmonis strain Austral-005 using multidimensional protein identification technology. The analyzes identified 87 proteins of different subcellular origins, such as the cytoplasmic and membrane compartment, where many of them have virulence functions. The other two prototypes activated only the innate immune responses, but did not protect Salmo salar against P. salmonis. These results suggest that the knowledge of the formulation of vaccines based on P. salmonis proteins is useful as an effective therapy, this demonstrates the importance of the different research tools to improve the study of the different immune responses, resistance to diseases in the Atlantic salmon. We suggest that this vaccine can help prevent widespread infection by P. salmonis, in addition to being able to be used as a booster after a primary vaccine to maintain high levels of circulating protective antibodies, greatly helping to reduce the economic losses caused by the pathogen.
Collapse
Affiliation(s)
- Juan Pablo Pontigo
- Laboratorio de Biotecnología Aplicada, Facultad de Medicina Veterianaria, Universidad San Sebastián, Puerto Montt, Chile
| | - Carla Espinoza
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Mauricio Hernandez
- Proteogenomics Laboratory, Molecular Epidemiology for Life of Science reseArch (MELISA) Institute, San Pedro de Paz, Chile
| | - Guillermo Nourdin
- Proteogenomics Laboratory, Molecular Epidemiology for Life of Science reseArch (MELISA) Institute, San Pedro de Paz, Chile
| | - Cristian Oliver
- Laboratorio de Biotecnología Acuática, Facultad de Ciencias Veterinarias. Universidad Austral de Chile, Valdivia, Chile
| | - Rubén Avendaño-Herrera
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile.,Laboratorio de Patología de Organismos Acuaticos y Biotecnologia Acuicola, Facultad de Ciencias Biologicas, Universidad Andres Bello, Viña del Mar, Chile
| | - Jaime Figueroa
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.,Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile
| | - Cecilia Rauch
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | | | - Luis Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile.,Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile
| | - Alejandro J Yáñez
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile.,Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| |
Collapse
|
6
|
Engineering a defined culture medium to grow Piscirickettsia salmonis for its use in vaccine formulations. ACTA ACUST UNITED AC 2020; 47:299-309. [DOI: 10.1007/s10295-020-02265-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 02/10/2020] [Indexed: 12/18/2022]
Abstract
Abstract
Piscirickettsia salmonis is a facultative Gram-negative intracellular bacterium that produces piscirickettsiosis, disease that causes a high negative impact in salmonid cultures. The so-far-unidentified nutritional requirements have hindered its axenic culture at laboratory and industrial scales for the formulation of vaccines. The present study describes the development of a defined culture medium for P. salmonis. The culture medium was formulated through rational design involving auxotrophy test and statistical designs of experiments, considering the genome-scale metabolic reconstruction of P. salmonis reported by our group. The whole optimization process allowed for a twofold increase in biomass and a reduction of about 50% of the amino acids added to the culture medium. The final culture medium contains twelve amino acids, where glutamic acid, threonine and arginine were the main carbon and energy sources, supporting 1.65 g/L of biomass using 6.5 g/L of amino acids in the formulation. These results will contribute significantly to the development of new operational strategies to culture this bacterium for the production of vaccines.
Collapse
|
7
|
Jia B, Delphino MKVC, Awosile B, Hewison T, Whittaker P, Morrison D, Kamaitis M, Siah A, Milligan B, Johnson SC, Gardner IA. Review of infectious agent occurrence in wild salmonids in British Columbia, Canada. JOURNAL OF FISH DISEASES 2020; 43:153-175. [PMID: 31742733 DOI: 10.1111/jfd.13084] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/22/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
Wild Pacific salmonids (WPS) are economically and culturally important to the Pacific North region. Most recently, some populations of WPS have been in decline. Of hypothesized factors contributing to the decline, infectious agents have been postulated to increase the risk of mortality in Pacific salmon. We present a literature review of both published journal and unpublished data to describe the distribution of infectious agents reported in wild Pacific salmonid populations in British Columbia (BC), Canada. We targeted 10 infectious agents, considered to potentially cause severe economic losses in Atlantic salmon or be of conservation concern for wild salmon in BC. The findings indicated a low frequency of infectious hematopoietic necrosis virus, piscine orthoreovirus, viral haemorrhagic septicaemia virus, Aeromonas salmonicida, Renibacterium salmoninarum, Piscirickettsia salmonis and other Rickettsia-like organisms, Yersinia ruckeri, Tenacibaculum maritimum and Moritella viscosa. No positive results were reported for infestations with Paramoeba perurans in peer-reviewed papers and the DFO Fish Pathology Program database. This review synthesizes existing information, as well as gaps therein, that can support the design and implementation of a long-term surveillance programme of infectious agents in wild salmonids in BC.
Collapse
Affiliation(s)
- Beibei Jia
- Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| | - Marina K V C Delphino
- Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| | - Babafela Awosile
- Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| | - Tim Hewison
- Grieg Seafood BC Ltd., Campbell River, BC, Canada
| | | | | | | | - Ahmed Siah
- British Columbia Centre for Aquatic Health Sciences, Campbell River, BC, Canada
| | | | - Stewart C Johnson
- Pacific Biological Station, Fisheries and Oceans Canada (DFO), Nanaimo, BC, Canada
| | - Ian A Gardner
- Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada
| |
Collapse
|
8
|
Tinelli A, Santacroce MP, Passantino G, Patruno R, Desantis S, Leone R, Gorgoni P, Zizzo N. Histological features of Rickettsia-like organisms in the European flat oyster (Ostrea edulis L.). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:882-889. [PMID: 31820245 DOI: 10.1007/s11356-019-07007-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 11/11/2019] [Indexed: 06/10/2023]
Abstract
The European flat oyster (Ostrea edulis L.) represents an economically important oyster production in Southern Italy, widespread in natural beds along the coast. The practice to be eaten raw is an everlasting concern for possible health risk with a need to stringently monitor the health of aquatic environment. A screening survey using histopathological examination was undertaken by harvesting O. edulis from different sites along the Apulian coast of Italy. Tissue samples of the digestive gland, kidney, gonad, and gill were provided for morphologic study in light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) analysis. The LM observations revealed spherical cytoplasmic inclusions as basophilic prokaryote colonies in 13/250 oysters. The TEM and SEM confirmed the presence of intracytoplasmic inclusions of Rickettsia-like organisms (RLOs), merely in the epithelial cells of the digestive gland tubule tissues in the 13 oysters. Within intracytoplasmic vacuoles, RLOs exhibited a prokaryotic characteristic ultrastructure with transverse binary fission, a DNA zone full of chromatin fibers and a granular periplasmic ribosome zone. O. edulis were found positive for RLOs in wild oysters from Manfredonia, while the other sites were found free of pathological inclusions. Thus, we present the first report of a Rickettsia-like infection in the Apulian wild oyster (O. edulis) from Italy, including an ultrastructural description and pathological characterization.
Collapse
Affiliation(s)
- Antonella Tinelli
- Department of Veterinary Medicine, Veterinary Pathology and Comparative Oncology Unit, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy.
| | - Maria Pia Santacroce
- Department of Veterinary Medicine, Veterinary Pathology and Comparative Oncology Unit, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy
| | - Giuseppe Passantino
- Department of Veterinary Medicine, Veterinary Pathology and Comparative Oncology Unit, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy
| | - Rosa Patruno
- Unit of Animal Health, ASL BAT, Corso Imbriani, 113, Trani, Italy
| | - Salvatore Desantis
- Department of Emergency and Organ Transplants (DETO), Section of Veterinary Science and Animal Production, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy
| | - Rosa Leone
- Department of Veterinary Medicine, Veterinary Pathology and Comparative Oncology Unit, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy
| | - Paola Gorgoni
- Department of Veterinary Medicine, Veterinary Pathology and Comparative Oncology Unit, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy
| | - Nicola Zizzo
- Department of Veterinary Medicine, Veterinary Pathology and Comparative Oncology Unit, University of Bari Aldo Moro, Valenzano, 70010, Bari, Italy
| |
Collapse
|
9
|
Martínez D, Vargas-Lagos C, Saravia J, Oyarzún R, Loncoman C, Pontigo JP, Vargas-Chacoff L. Cellular stress responses of Eleginops maclovinus fish injected with Piscirickettsia salmonis and submitted to thermal stress. Cell Stress Chaperones 2020; 25:93-104. [PMID: 31834618 PMCID: PMC6985426 DOI: 10.1007/s12192-019-01051-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 10/25/2019] [Accepted: 10/31/2019] [Indexed: 12/15/2022] Open
Abstract
Fluctuations in ambient temperature along with the presence of pathogenic microorganisms can induce important cellular changes that alter the homeostasis of ectothermic fish. The aim of this study was to evaluate how sudden or gradual changes in environmental temperature together with the administration of Piscirickettsia salmonis modulate the transcription of genes involved in cellular stress response in the liver of Eleginops maclovinus. Fish were subjected to the following experimental conditions in duplicate: C- 12 °C: Injection only with culture medium, C+ 12 °C: Injection with P. salmonis, AM 18 °C: Injection only with culture medium under acclimation at 18 °C, AB 18 °C: Injection with P. salmonis under acclimation at 18 °C, SM 18 °C: Injection only with culture medium and thermal shock at 18 °C and SB 18 °C: Injection with P. salmonis and thermal shock at 18 °C and sampling at 4-, 8-, 12-, 16- and 20-day post injection (dpi). The genes implied in the heat shock response (HSP70, HSC70, HSP90, and GRP78), apoptosis pathway (BAX and SMAC/Diablo), ubiquitination (E2, E3, ubiquitin, and CHIP), and 26 proteasome complex (PSMB7, PSMC1, and PSMA2) showed expression profiles dependent on time and type of injection applied. All the genes greatly increased their expression levels at day 16 and showed moderate increases at day 20, except for PSMA2 which showed a higher increase between 4- and 12-day post challenges. Our results suggest that the changes observed at the final days of the experiment are due to temperature more than P. salmonis.
Collapse
Affiliation(s)
- D Martínez
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile.
- Escuela de Graduados, Programa de Doctorado en Ciencias de la Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile.
- Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, casilla, 567, Valdivia, Chile.
| | - C Vargas-Lagos
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, casilla, 567, Valdivia, Chile
- Escuela de Graduados, Programa de Magister en Microbiología, Universidad Austral de Chile, Valdivia, Chile
- Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile
| | - J Saravia
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
- Escuela de Graduados, Programa de Doctorado en Ciencias de la Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile
- Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, casilla, 567, Valdivia, Chile
| | - R Oyarzún
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
- Escuela de Graduados, Programa de Doctorado en Ciencias de la Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile
- Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, casilla, 567, Valdivia, Chile
| | - C Loncoman
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
| | - J P Pontigo
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
| | - L Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile.
- Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, casilla, 567, Valdivia, Chile.
| |
Collapse
|
10
|
Meza K, Inami M, Dalum AS, Bjelland AM, Sørum H, Løvoll M. Development of piscirickettsiosis in Atlantic salmon (Salmo salar L.) smolts after intraperitoneal and cohabitant challenge using an EM90-like isolate: A comparative study. JOURNAL OF FISH DISEASES 2019; 42:1001-1011. [PMID: 30977526 DOI: 10.1111/jfd.13004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/11/2019] [Accepted: 03/14/2019] [Indexed: 06/09/2023]
Abstract
Piscirickettsiosis, caused by the intracellular Gram-negative bacteria Piscirickettsia salmonis, is at present the most devastating disease in the Chilean salmon industry. The aim of this study was to analyse disease development after challenge with a P. salmonis strain (EM90-like) under a controlled environment by comparing intraperitoneal challenge with cohabitation challenge. The P. salmonis EM90-like isolate was cultured in a liquid medium for the challenge of 400 Atlantic salmon (Salmo salar) smolts. Cumulative mortality was registered, necropsy was performed, and bacterial distribution in the tissues and histopathological changes were analysed. The results revealed a similar progression of the disease for the two different challenge models. Pathological and histopathological changes became more visible during the development of the clinical phase of the disease. Bacterial DNA was identified in all the analysed tissues indicating a systemic infection. Bacterial tropism to visceral organs was demonstrated by real-time quantitative PCR and immunohistochemistry. Better knowledge of disease development during P. salmonis infection may contribute to further development of challenge models that mimic the field situation during piscirickettsiosis outbreaks. The models can be used to develop and test future preventive measures against the disease.
Collapse
Affiliation(s)
- Karla Meza
- VESO Vikan, Namsos, Norway
- Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | | | | | - Ane M Bjelland
- Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | - Henning Sørum
- Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | | |
Collapse
|
11
|
Martínez D, Vargas-Lagos C, Oyarzún R, Loncoman CA, Pontigo JP, Yáñez AJ, Vargas-Chacoff L. Temperature modulates the immunological response of the sub-antarctic notothenioid fish Eleginops maclovinus injected with Piscirickettsia salmonis. FISH & SHELLFISH IMMUNOLOGY 2018; 82:492-503. [PMID: 30165153 DOI: 10.1016/j.fsi.2018.08.042] [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: 06/30/2018] [Revised: 08/05/2018] [Accepted: 08/19/2018] [Indexed: 06/08/2023]
Abstract
Eleginops maclovinus is a eurythermic fish that under natural conditions lives in environments with temperatures ranging from 4 to 18 °C and can be usually captured near salmon farming areas. The aim of this study was to evaluate the effect of temperature over the innate and adaptive immune response of E. maclovinus challenged with Piscirickettsia salmonis following different treatments: C (control injection with culture medium at 12 °C), C+ (bacterial injection at 12 °C), 18 °C c/A + B (injection with culture medium in acclimation at 18 °C), 18 °C c/A + B (bacterial injection in acclimation at 18 °C), 18 °C s/A + M (injection with culture medium without acclimation at 18 °C) and 18 °C s/A + B (bacterial injection without acclimation at 18 °C). Each injection had 100 μL of culture medium or with 100 μL at a concentration 1 × 108 of live bacteria, sampling six fish per group at 4, 8, 12, 16 and 20 days post-injection (dpi). Expression of the mRNA related with the innate immune response gene (TLR1, TLR5, TLR8, NLRC3, NLRC5, MyD88 and IL-1β) as well as the adaptive immune response gene (MHCI, MHCII, IgMs and IgD) were measured in spleen and head kidney. Gene expression profiles were treatment-type and time dependent. Levels of Immunoglobulin M (IgM) increased in challenged groups with P. salmonis from day 8-20 post challenge, which suggest activation of B cells IgM + through P. salmonis epitope detection. Additionally, a rise in temperature from 12 °C (C+) to 18 °C (with/without acclimation) also resulted in antibody increment detected in serum with significant differences between "18 °C c/A + B" and "18 °C s/A + B" groups. This is the first study that evaluates the effect of temperature changes and mRNA expression related with immune system gene over time on E. maclovinus, a native wild life fish that cohabits in the salmon farming environment.
Collapse
Affiliation(s)
- D Martínez
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Escuela de Graduados, Programa de Doctorado en Ciencias de l6a Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de C'hile, Casilla 567, Valdivia, Chile.
| | - C Vargas-Lagos
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de C'hile, Casilla 567, Valdivia, Chile; Escuela de Graduados, Programa de Magister en Microbiología, Universidad Austral de Chile, Valdivia, Chile
| | - R Oyarzún
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Escuela de Graduados, Programa de Doctorado en Ciencias de l6a Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de C'hile, Casilla 567, Valdivia, Chile
| | - C A Loncoman
- Asia Pacific Centre for Animal Health, Faculty of Veterinary Science, University of Melbourne, Melbourne, Australia; Applied Biochemistry Laboratory, Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - J P Pontigo
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
| | - A J Yáñez
- Centro Fondap Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Austral de Chile, Valdivia, Chile; Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
| | - L Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de C'hile, Casilla 567, Valdivia, Chile.
| |
Collapse
|
12
|
Higuera-Llantén S, Vásquez-Ponce F, Barrientos-Espinoza B, Mardones FO, Marshall SH, Olivares-Pacheco J. Extended antibiotic treatment in salmon farms select multiresistant gut bacteria with a high prevalence of antibiotic resistance genes. PLoS One 2018; 13:e0203641. [PMID: 30204782 PMCID: PMC6133359 DOI: 10.1371/journal.pone.0203641] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 08/26/2018] [Indexed: 01/31/2023] Open
Abstract
The high use of antibiotics for the treatment of bacterial diseases is one of the main problems in the mass production of animal protein. Salmon farming in Chile is a clear example of the above statement, where more than 5,500 tonnes of antibiotics have been used over the last 10 years. This has caused a great impact both at the production level and on the environment; however, there are still few works in relation to it. In order to demonstrate the impact of the high use of antibiotics on fish gut microbiota, we have selected four salmon farms presenting a similar amount of fish of the Atlantic salmon species (Salmo salar), ranging from 4,500 to 6,000 tonnes. All of these farms used treatments with high doses of antibiotics. Thus, 15 healthy fish were selected and euthanised in order to isolate the bacteria resistant to the antibiotics oxytetracycline and florfenicol from the gut microbiota. In total, 47 bacterial isolates resistant to florfenicol and 44 resistant to oxytetracycline were isolated, among which isolates with Minimum Inhibitory Concentrations (MIC) exceeding 2048 μg/mL for florfenicol and 1024 μg/mL for oxytetracycline were found. In addition, another six different antibiotics were tested in order to demonstrate the multiresistance phenomenon. In this regard, six isolates of 91 showed elevated resistance values for the eight tested antibiotics, including florfenicol and oxytetracycline, were found. These bacteria were called “super-resistant” bacteria. This phenotypic resistance was verified at a genotypic level since most isolates showed antibiotic resistance genes (ARGs) to florfenicol and oxytetracycline. Specifically, 77% of antibiotic resistant bacteria showed at least one gene resistant to florfenicol and 89% showed at least one gene resistant to oxytetracycline. In the present study, it was demonstrated that the high use of the antibiotics florfenicol and oxytetracycline has, as a consequence, the selection of multiresistant bacteria in the gut microbiota of farmed fish of the Salmo salar species at the seawater stage. Also, the phenotypic resistance of these bacteria can be correlated with the presence of antibiotic resistance genes.
Collapse
MESH Headings
- Animals
- Anti-Bacterial Agents/pharmacology
- Aquaculture
- Bacteria/drug effects
- Bacteria/genetics
- Bacteria/isolation & purification
- Drug Resistance, Multiple, Bacterial/drug effects
- Drug Resistance, Multiple, Bacterial/genetics
- Gastrointestinal Microbiome/drug effects
- Intestines/microbiology
- Microbial Sensitivity Tests
- Oxytetracycline/pharmacology
- RNA, Ribosomal, 16S/chemistry
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 16S/metabolism
- Salmo salar
- Thiamphenicol/analogs & derivatives
- Thiamphenicol/pharmacology
Collapse
Affiliation(s)
- Sebastián Higuera-Llantén
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Valparaíso, CP, Chile
| | - Felipe Vásquez-Ponce
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Valparaíso, CP, Chile
| | - Beatriz Barrientos-Espinoza
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Valparaíso, CP, Chile
| | - Fernando O. Mardones
- Escuela de Medicina Veterinaria, Facultad de Ecología y Recursos Naturales, Universidad Andrés Bello, Republica 252, CP, Santiago, Chile
| | - Sergio H. Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Valparaíso, CP, Chile
| | - Jorge Olivares-Pacheco
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Campus Curauma, Valparaíso, CP, Chile
- Millenium Nucleus on Interdisciplinary approach to Antimicrobial Resistance, Lo Barnechea, Santiago, CP, Chile
- * E-mail:
| |
Collapse
|
13
|
Flores-Herrera P, Arredondo-Zelada O, Marshall SH, Gómez FA. Selection and validation of reliable housekeeping genes to evaluate Piscirickettsia salmonis gene expression. INFECTION GENETICS AND EVOLUTION 2018; 63:151-157. [PMID: 29860100 DOI: 10.1016/j.meegid.2018.05.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 05/15/2018] [Accepted: 05/30/2018] [Indexed: 12/30/2022]
Abstract
Piscirickettsia salmonis is a highly aggressive facultative intracellular bacterium that challenges the sustainability of Chilean salmon production. Due to the limited knowledge of its biology, there is a need to identify key molecular markers that could help define the pathogenic potential of this bacterium. We think a model system should be implemented that efficiently evaluates the expression of putative bacterial markers by using validated, stable, and highly specific housekeeping genes to properly select target genes, which could lead to identifying those responsible for infection and disease induction in naturally infected fish. Here, we selected a set of validated reference or housekeeping genes for RT-qPCR expression analyses of P. salmonis under different growth and stress conditions, including an in vitro infection kinetic. After a thorough screening, we selected sdhA as the most reliable housekeeping gene able to represent stable and highly specific host reference genes for RT-qPCR-driven P. salmonis analysis.
Collapse
Affiliation(s)
- Patricio Flores-Herrera
- 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
| | - Sergio H Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330 Curauma, Valparaíso, Chile.
| | - Fernando A Gómez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Av. Universidad 330 Curauma, Valparaíso, Chile.
| |
Collapse
|
14
|
Martínez D, Díaz-Ibarrola D, Vargas-Lagos C, Oyarzún R, Pontigo JP, Muñoz JLP, Yáñez AJ, Vargas-Chacoff L. Immunological response of the Sub-Antarctic Notothenioid fish Eleginops maclovinus injected with two strains of Piscirickettsia salmonis. FISH & SHELLFISH IMMUNOLOGY 2018; 75:139-148. [PMID: 29421586 DOI: 10.1016/j.fsi.2018.01.012] [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] [Received: 11/08/2017] [Revised: 01/03/2018] [Accepted: 01/11/2018] [Indexed: 06/08/2023]
Abstract
Eleginops maclovinus is an endemic fish to Chile that lives in proximity to salmonid culture centers, feeding off of uneaten pellet and salmonid feces. Occurring in the natural environment, this interaction between native and farmed fish could result in the horizontal transmission of pathogens affecting the aquaculture industry. The aim of this study was to evaluate the innate and adaptive immune responses of E. maclovinus challenged with P. salmonis. Treatment injections (in duplicate) were as follows: control (100 μL of culture medium), wild type LF-89 strain (100 μL, 1 × 108 live bacteria), and antibiotic resistant strain Austral-005 (100 μL, 1 × 108 live bacteria). The fish were sampled at various time-points during the 35-day experimental period. The gene expression of TLRs (1, 5, and 8), NLRCs (3 and 5), C3, IL-1β, MHCII, and IgMs were significantly modulated during the experimental period in both the spleen and gut (excepting TLR1 and TLR8 spleen expressions), with tissue-specific expression profiles and punctual differences between the injected strains. Anti-P. salmonis antibodies increased in E. maclovinus serum from day 14-28 for the LF-89 strain and from day 14-35 for the Austral-005 strain. These results suggest temporal activation of the innate and adaptive immune responses in E. maclovinus tissues when injected by distinct P. salmonis strains. The Austral-005 strain did not always cause the greatest increases/decreases in the number of transcripts, so the magnitude of the observed immune response (mRNA) may not be related to antibiotic resistance. This is the first immunological study to relate a pathogen widely studied in salmonids with a native fish.
Collapse
Affiliation(s)
- D Martínez
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Escuela de Graduados, Programa de Doctorado en Ciencias de l6a Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
| | - D Díaz-Ibarrola
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
| | - C Vargas-Lagos
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Escuela de Graduados, Programa de Magister en Microbiología, Universidad Austral de Chile, Valdivia, Chile; Centro Fondap Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Austral de Chile, Valdivia, Chile
| | - R Oyarzún
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Escuela de Graduados, Programa de Doctorado en Ciencias de l6a Acuicultura, Universidad Austral de Chile, Av. Los Pinos s/n Balneario Pelluco, Puerto Montt, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - J P Pontigo
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile
| | - J L P Muñoz
- Centro de Investigación y Desarrollo i ∼ mar, Universidad de los Lagos, Casilla 557, Puerto Montt, Chile
| | - A J Yáñez
- Centro Fondap Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Austral de Chile, Valdivia, Chile; Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
| | - L Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Laboratorio de Fisiología de Peces, Universidad Austral de Chile, Valdivia, Chile; Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Casilla 567, Valdivia, Chile.
| |
Collapse
|
15
|
Marcos-López M, Ruane NM, Scholz F, Bolton-Warberg M, Mitchell SO, Murphy O'Sullivan S, Irwin Moore A, Rodger HD. Piscirickettsia salmonis infection in cultured lumpfish (Cyclopterus lumpus L.). JOURNAL OF FISH DISEASES 2017; 40:1625-1634. [PMID: 28429818 DOI: 10.1111/jfd.12630] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/07/2017] [Accepted: 02/09/2017] [Indexed: 06/07/2023]
Abstract
A Piscirickettsia salmonis infection was diagnosed in lumpfish (Cyclopterus lumpus L.) juveniles held in a marine research facility on the west coast of Ireland. The main clinical signs and pathology included marked ascites, severe multifocal liver necrosis and severe diffuse inflammation and necrosis of the exocrine pancreas and peri-pancreatic adipose tissue. Numerous Piscirickettsia-like organisms were observed by histopathology in the affected organs, and the bacterial species was characterized by molecular analysis. Sequencing of the partial 16S rDNA gene and internal transcribed spacer region showed the lumpfish sequences to be closely related to previously identified Atlantic salmon (Salmo salar L.) sequences from Ireland. To the authors' knowledge, this is the first detection of P. salmonis in lumpfish worldwide. The infection is considered potentially significant in terms of lumpfish health and biosecurity.
Collapse
Affiliation(s)
| | - N M Ruane
- Fish Health Unit, Marine Institute, Oranmore, Co. Galway, Ireland
| | - F Scholz
- Fish Vet Group Ireland, Galway, Ireland
| | - M Bolton-Warberg
- Carna Research Station, Ryan Institute, NUIG, Carna, Co. Galway, Ireland
| | | | | | - A Irwin Moore
- Carna Research Station, Ryan Institute, NUIG, Carna, Co. Galway, Ireland
| | | |
Collapse
|
16
|
Nourdin-Galindo G, Sánchez P, Molina CF, Espinoza-Rojas DA, Oliver C, Ruiz P, Vargas-Chacoff L, Cárcamo JG, Figueroa JE, Mancilla M, Maracaja-Coutinho V, Yañez AJ. Comparative Pan-Genome Analysis of Piscirickettsia salmonis Reveals Genomic Divergences within Genogroups. Front Cell Infect Microbiol 2017; 7:459. [PMID: 29164068 PMCID: PMC5671498 DOI: 10.3389/fcimb.2017.00459] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/16/2017] [Indexed: 11/13/2022] Open
Abstract
Piscirickettsia salmonis is the etiological agent of salmonid rickettsial septicemia, a disease that seriously affects the salmonid industry. Despite efforts to genomically characterize P. salmonis, functional information on the life cycle, pathogenesis mechanisms, diagnosis, treatment, and control of this fish pathogen remain lacking. To address this knowledge gap, the present study conducted an in silico pan-genome analysis of 19 P. salmonis strains from distinct geographic locations and genogroups. Results revealed an expected open pan-genome of 3,463 genes and a core-genome of 1,732 genes. Two marked genogroups were identified, as confirmed by phylogenetic and phylogenomic relationships to the LF-89 and EM-90 reference strains, as well as by assessments of genomic structures. Different structural configurations were found for the six identified copies of the ribosomal operon in the P. salmonis genome, indicating translocation throughout the genetic material. Chromosomal divergences in genomic localization and quantity of genetic cassettes were also found for the Dot/Icm type IVB secretion system. To determine divergences between core-genomes, additional pan-genome descriptions were compiled for the so-termed LF and EM genogroups. Open pan-genomes composed of 2,924 and 2,778 genes and core-genomes composed of 2,170 and 2,228 genes were respectively found for the LF and EM genogroups. The core-genomes were functionally annotated using the Gene Ontology, KEGG, and Virulence Factor databases, revealing the presence of several shared groups of genes related to basic function of intracellular survival and bacterial pathogenesis. Additionally, the specific pan-genomes for the LF and EM genogroups were defined, resulting in the identification of 148 and 273 exclusive proteins, respectively. Notably, specific virulence factors linked to adherence, colonization, invasion factors, and endotoxins were established. The obtained data suggest that these genes could be directly associated with inter-genogroup differences in pathogenesis and host-pathogen interactions, information that could be useful in designing novel strategies for diagnosing and controlling P. salmonis infection.
Collapse
Affiliation(s)
- Guillermo Nourdin-Galindo
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Laboratory of Integrative Bioinformatics, Facultad de Ciencias, Centro de Genómica y Bioinformática, Universidad Mayor, Santiago, Chile
| | - Patricio Sánchez
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP, Interdisciplinary Center for Aquaculture Research, Concepción, Chile
| | - Cristian F Molina
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,AUSTRAL-omics, Universidad Austral de Chile, Valdivia, Chile
| | - Daniela A Espinoza-Rojas
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Laboratory of Integrative Bioinformatics, Facultad de Ciencias, Centro de Genómica y Bioinformática, Universidad Mayor, Santiago, Chile
| | - Cristian Oliver
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP, Interdisciplinary Center for Aquaculture Research, Concepción, Chile.,Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola, Facultad de Ciencias Biológicas, Universidad Andrés Bello, Viña del Mar, Chile
| | - Pamela Ruiz
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP, Interdisciplinary Center for Aquaculture Research, Concepción, Chile
| | - Luis Vargas-Chacoff
- Facultad de Ciencias, Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - Juan G Cárcamo
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP, Interdisciplinary Center for Aquaculture Research, Concepción, Chile
| | - Jaime E Figueroa
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP, Interdisciplinary Center for Aquaculture Research, Concepción, Chile
| | - Marcos Mancilla
- Laboratorio de Diagnóstico y Biotecnología, ADL Diagnostic Chile SpA., Puerto Montt, Chile
| | - Vinicius Maracaja-Coutinho
- Laboratory of Integrative Bioinformatics, Facultad de Ciencias, Centro de Genómica y Bioinformática, Universidad Mayor, Santiago, Chile.,Laboratory of Integrative Bioinformatics, Instituto Vandique, João Pessoa, Brazil.,Beagle Bioinformatics, Santiago, Chile
| | - Alejandro J Yañez
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile.,Centro FONDAP, Interdisciplinary Center for Aquaculture Research, Concepción, Chile.,AUSTRAL-omics, Universidad Austral de Chile, Valdivia, Chile
| |
Collapse
|
17
|
Martínez D, Oyarzún R, Pontigo JP, Romero A, Yáñez AJ, Vargas-Chacoff L. Nutritional Immunity Triggers the Modulation of Iron Metabolism Genes in the Sub-Antarctic Notothenioid Eleginops maclovinus in Response to Piscirickettsia salmonis. Front Immunol 2017; 8:1153. [PMID: 28974951 PMCID: PMC5610722 DOI: 10.3389/fimmu.2017.01153] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 08/31/2017] [Indexed: 12/21/2022] Open
Abstract
Iron deprivation is a nutritional immunity mechanism through which fish can limit the amount of iron available to invading bacteria. The aim of this study was to evaluate the modulation of iron metabolism genes in the liver and brain of sub-Antarctic notothenioid Eleginops maclovinus challenged with Piscirickettsia salmonis. The specimens were inoculated with two P. salmonis strains: LF-89 (ATCC® VR-1361™) and Austral-005 (antibiotic resistant). Hepatic and brain samples were collected at intervals over a period of 35 days. Gene expression (by RT-qPCR) of proteins involved in iron storage, transport, and binding were statistically modulated in infected fish when compared with control counterparts. Specifically, the expression profiles of the transferrin and hemopexin genes in the liver, as well as the expression profiles of ferritin-M, ferritin-L, and transferrin in the brain, were similar for both experimental groups. Nevertheless, the remaining genes such as ferritin-H, ceruloplasmin, hepcidin, and haptoglobin presented tissue-specific expression profiles that varied in relation to the injected bacterial strain and sampling time-point. These results suggest that nutritional immunity could be an important immune defense mechanism for E. maclovinus against P. salmonis injection. This study provides relevant information for understanding iron metabolism of a sub-Antarctic notothenioid fish.
Collapse
Affiliation(s)
- Danixa Martínez
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile.,Escuela de Graduados, Programa de Doctorado en Ciencias de la Acuicultura, Universidad Austral de Chile, Puerto Montt, Chile.,Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile
| | - Ricardo Oyarzún
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile.,Escuela de Graduados, Programa de Doctorado en Ciencias de la Acuicultura, Universidad Austral de Chile, Puerto Montt, Chile.,Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile
| | - Juan Pablo Pontigo
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - Alex Romero
- Centro Fondap Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Austral de Chile, Valdivia, Chile.,Instituto de Patología Animal, Universidad Austral de Chile, Valdivia, Chile
| | - Alejandro J Yáñez
- Centro Fondap Interdisciplinary Center for Aquaculture Research (INCAR), Universidad Austral de Chile, Valdivia, Chile.,Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile
| | - Luis Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile.,Centro Fondap de Investigación de Altas Latitudes (IDEAL), Universidad Austral de Chile, Valdivia, Chile
| |
Collapse
|
18
|
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.
Collapse
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
| | | | | |
Collapse
|
19
|
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.
Collapse
Affiliation(s)
- R N Morrison
- Animal Health Laboratories, Department of Primary Industries, Parks, Water and Environment (DPIPWE), Launceston, Tasmania 7250, Australia
| | | | | | | | | |
Collapse
|
20
|
Evensen Ø. Immunization Strategies against Piscirickettsia salmonis Infections: Review of Vaccination Approaches and Modalities and Their Associated Immune Response Profiles. Front Immunol 2016; 7:482. [PMID: 27917172 PMCID: PMC5114462 DOI: 10.3389/fimmu.2016.00482] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 10/20/2016] [Indexed: 12/29/2022] Open
Abstract
Salmonid rickettsial septicemia (SRS) is a serious, infectious disease in Chilean salmon farming caused by Piscirickettsia salmonis, causing heavy losses to the salmonid industry. P. salmonis belongs to the Gammaproteobacteria, order Thiotrichales. SRS was first described in Chile in 1989, and infection with P. salmonis has since been described from a high number of fish species and in several geographic regions globally. P. salmonis infection of salmonids causes multifocal, necrotic areas of internal organs such as liver, kidney, and spleen. Histologically and immunologically, the tissue response is the formation of granulomas, often with central suppuration. The exact sequence of infection is not known, but bacteria likely gain access to internal organs through mucosal surfaces and when infected, fish carry bacteria in macrophages. It has not been fully determined if the bacterium resides in the cytosol or “hide” within vesicular structures intracellularly, although there are indications that in vitro infection results in actin reorganization and formation of actin-coated vesicle within which the bacterium resides. Protection against lethal challenge is well documented in lab scale experiments, but protection from vaccination has proven more difficult to attain long term under field conditions. Current vaccination protocols include whole cell, inactivated and adjuvanted vaccines for injection for primary immunization followed by oral boost where timing of boost delivery is followed by measuring circulating antibody levels against the pathogen. Documentation also exist that there is correlation between antibody titers and protection against mortality. Future vaccination regimes will likely also include live-attenuated vaccines or other technologies such as DNA vaccination. So far, there is no documentation available for live vaccines and, for DNA vaccines, studies have been unsuccessful under laboratory conditions.
Collapse
Affiliation(s)
- Øystein Evensen
- Faculty of Veterinary Medicine and Biosciences, Norwegian University of Life Sciences , Oslo , Norway
| |
Collapse
|
21
|
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.
Collapse
|
22
|
Electrochemical detection of Piscirickettsia salmonis genomic DNA from salmon samples using solid-phase recombinase polymerase amplification. Anal Bioanal Chem 2016; 408:8611-8620. [PMID: 27220649 DOI: 10.1007/s00216-016-9639-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 05/13/2016] [Indexed: 10/21/2022]
Abstract
Electrochemical detection of solid-phase isothermal recombinase polymerase amplification (RPA) of Piscirickettsia salmonis in salmon genomic DNA is reported. The electrochemical biosensor was constructed by surface functionalization of gold electrodes with a thiolated forward primer specific to the genomic region of interest. Solid-phase RPA and primer elongation were achieved in the presence of the specific target sequence and biotinylated reverse primers. The formation of the subsequent surface-tethered duplex amplicons was electrochemically monitored via addition of streptavidin-linked HRP upon completion of solid-phase RPA. Successful quantitative amplification and detection were achieved in less than 1 h at 37 °C, calibrating with PCR-amplified genomic DNA standards and achieving a limit of detection of 5 · 10-8 μg ml-1 (3 · 103 copies in 10 μl). The presented system was applied to the analysis of eight real salmon samples, and the method was also compared to qPCR analysis, observing an excellent degree of correlation. Graphical abstract Schematic of use of electrochemical RPA for detection of Psiricketessia salmonis in salmon liver.
Collapse
|
23
|
Contreras-Lynch S, Olmos P, Vargas A, Figueroa J, González-Stegmaier R, Enríquez R, Romero A. Identification and genetic characterization of Piscirickettsia salmonis in native fish from southern Chile. DISEASES OF AQUATIC ORGANISMS 2015; 115:233-244. [PMID: 26290508 DOI: 10.3354/dao02892] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Piscirickettsia salmonis is the etiological agent of piscirickettsiosis, a severe disease causing high mortalities in salmonids. This bacterium has been previously identified and isolated in all cultivated salmonids in Chile and worldwide, including Salmo salar, Oncorhynchus kisutch, and O. mykiss, in addition to being found in non-salmonid species such as Dicentrarchus labrax and Atractoscion nobilis. In this study, the 16S rRNA gene and intergenic spacer ITS-1 of P. salmonis were amplified by PCR from DNA samples extracted from the native Chilean fish species Eleginops maclovinus, Odontesthes regia, Sebastes capensis, and Salilota australis. Analysis of the 16S rRNA sequences from O. regia demonstrated a close phylogenetic relationship with the 16S rRNA gene in the Chilean EM-90 strain. The 16S rRNA sequences from E. maclovinus, S. capensis, and S. australis were related to the Chilean LF-89 sequence and Scottish strains. To confirm these findings, analysis of P. salmonis ITS-1 sequences obtained from the 4 sampled native species demonstrated a high degree of identity and a close phylogenetic relationship with Chilean P. salmonis sequences, including LF-89 and EM-90. These results suggest a strong relationship between the nucleotide sequences from the 16S rRNA and ITS-1 genes amplified from native fish with those sequences described in the first P. salmonis strains to be identified and isolated in Chile.
Collapse
|
24
|
Oliver C, Valenzuela K, Silva H, Haro R, Cortés M, Sandoval R, Pontigo J, Álvarez C, Figueroa J, Avendaño-Herrera R, Troncoso J, Yáñez A. Effectiveness of egg yolk immunoglobulin against the intracellular salmonid pathogen Piscirickettsia salmonis. J Appl Microbiol 2015; 119:365-76. [DOI: 10.1111/jam.12857] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 05/14/2015] [Accepted: 05/18/2015] [Indexed: 11/28/2022]
Affiliation(s)
- C. Oliver
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - K. Valenzuela
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - H. Silva
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - R.E. Haro
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - M. Cortés
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - R. Sandoval
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - J.P. Pontigo
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - C. Álvarez
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
| | - J.E. Figueroa
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
- Interdisciplinary Center for Aquaculture Research (INCAR); Concepción Chile
| | - R. Avendaño-Herrera
- Interdisciplinary Center for Aquaculture Research (INCAR); Concepción Chile
- Laboratorio de Patología de Organismos Acuáticos y Biotecnología Acuícola; Departamento de Ciencias Biológicas; Facultad de Ciencias Biológicas; Universidad Andrés Bello; Viña del Mar Chile
- Centro de Investigación Marina Quintay (CIMARQ); Quintay Chile
| | | | - A.J. Yáñez
- Instituto de Bioquímica y Microbiología; Facultad de Ciencias; Universidad Austral de Chile; Valdivia Chile
- Interdisciplinary Center for Aquaculture Research (INCAR); Concepción Chile
| |
Collapse
|
25
|
Ramírez R, Gómez FA, Marshall SH. The infection process of Piscirickettsia salmonis in fish macrophages is dependent upon interaction with host-cell clathrin and actin. FEMS Microbiol Lett 2014; 362:1-8. [PMID: 25790493 DOI: 10.1093/femsle/fnu012] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Piscirickettsia salmonis is an aggressive fish pathogen that causes Piscirickettsiosis, a systemic disease that threatens the sustainability of salmon production in Chile. To date, the infection strategies of this bacterium are poorly characterized, a Dot/Icm Type IV Secretion System homolog for intracellular multiplication and survival in macrophages is suggested. Since an invading pathogen and its host develop a complex interaction in which the pathogen strives to survive and replicate, while the host tries to eliminate infected cells and the invading pathogen, we decided to evaluate how the bacterium enters macrophages, its preferred target in vivo, and to follow its fate while struggling with its host using actin cytoskeleton as a molecular marker. We were able to demonstrate that clathrin is required for internalization and that actin cytoskeleton plays a demonstrative role throughout the infective process. Indeed, unlike other fish pathogens, P. salmonis fully exploits the actin monomers both from the disorganized cytoskeleton and an apparently pathogen-induced de novo synthesis of actin, generating tridimensional vacuoles that are increasingly detected at later stages of infection. We expect our results to contribute to a better understanding of the pathogenesis of this important fish pathogen.
Collapse
Affiliation(s)
- Ramón Ramírez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Curauma, Valparaíso, Chile Fraunhofer Chile Research Foundation, Center For Systems Biotechnology, Avenida M. Sánchez Fontecilla 310, Piso 14. Las Condes Santiago, Chile
| | - Fernando A Gómez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Curauma, Valparaíso, Chile
| | - Sergio H Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Curauma, Valparaíso, Chile NBC, Núcleo de Biotecnología Curauma, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Curauma, Valparaíso, Chile Fraunhofer Chile Research Foundation, Center For Systems Biotechnology, Avenida M. Sánchez Fontecilla 310, Piso 14. Las Condes Santiago, Chile
| |
Collapse
|
26
|
Vargas-Chacoff L, Ortíz E, Oyarzún R, Martínez D, Saavedra E, Sá R, Olavarría V, Nualart D, Yáñez A, Bertrán C, Mancera JM. Stocking density and Piscirickettsia salmonis infection effect on Patagonian blennie (Eleginops maclovinus, Cuvier 1830) skeletal muscle intermediate metabolism. FISH PHYSIOLOGY AND BIOCHEMISTRY 2014; 40:1683-1691. [PMID: 25034336 DOI: 10.1007/s10695-014-9959-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 06/24/2014] [Indexed: 06/03/2023]
Abstract
The need to expand aquaculture production has led to other fish to be considered as potential species for culture, such as the sub-Antarctic notothenioid Eleginops maclovinus (Valenciennes, 1830). The aim of this study was to determine the cumulative effect of density and pathogen infection by protein extract of Piscirickettsia salmonis on skeletal muscle metabolism. In a first experiment, specimens were submitted to three different stocking densities: (1) 3.1 kg m(-3), (2) 15 kg m(-3) and (3) 60 kg m(-3), for a period of 10 days. In a second experiment, metabolic changes caused by an infection of P. salmonis protein extract (a single injection of 0.5 μL P. salmonis protein extract g body weight(-1) was inoculated in the fish) and its combined effect with stocking density was assessed during a period of 10 days. This study concludes that stress caused by high stocking density led to the reorganization of some metabolic routes to fulfill skeletal muscle energy needs. Furthermore, infection response by pathogen P. salmonis differed when stocking density increased, suggesting an increase of energy needs with density in skeletal muscle of infected fish.
Collapse
Affiliation(s)
- L Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile,
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Draft Genome Sequence of Virulent Strain AUSTRAL-005 of Piscirickettsia salmonis, the Etiological Agent of Piscirickettsiosis. GENOME ANNOUNCEMENTS 2014; 2:2/5/e00990-14. [PMID: 25323708 PMCID: PMC4200146 DOI: 10.1128/genomea.00990-14] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [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 lethal pathogen of farmed salmonids, Piscirickettsia salmonis strain AUSTRAL-005. This virulent strain was isolated in 2008 from Oncorhynchus mykiss farms, and multiple genes involved in pathogenicity, environmental adaptation, and metabolic pathways were identified.
Collapse
|
28
|
Yáñez AJ, Valenzuela K, Matzner C, Olavarría V, Figueroa J, Avendaño-Herrera R, Carcamo JG. Broth microdilution protocol for minimum inhibitory concentration (MIC) determinations of the intracellular salmonid pathogen Piscirickettsia salmonis to florfenicol and oxytetracycline. JOURNAL OF FISH DISEASES 2014; 37:505-9. [PMID: 23803014 DOI: 10.1111/jfd.12144] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 05/07/2013] [Accepted: 05/17/2013] [Indexed: 05/12/2023]
Affiliation(s)
- A J Yáñez
- Facultad de Ciencias, Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Valdivia, Chile; Interdisciplinary Center for Aquaculture Research (INCAR), Concepción, Chile
| | | | | | | | | | | | | |
Collapse
|
29
|
Rozas M, Enríquez R. Piscirickettsiosis and Piscirickettsia salmonis in fish: a review. JOURNAL OF FISH DISEASES 2014; 37:163-88. [PMID: 24279295 DOI: 10.1111/jfd.12211] [Citation(s) in RCA: 161] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 10/18/2013] [Accepted: 10/19/2013] [Indexed: 05/03/2023]
Abstract
The bacterium Piscirickettsia salmonis is the aetiological agent of piscirickettsiosis a severe disease that has caused major economic losses in the aquaculture industry since its appearance in 1989. Recent reports of P. salmonis or P. salmonis-like organisms in new fish hosts and geographical regions have increased interest in the bacterium. Because this gram-negative bacterium is still poorly understood, many relevant aspects of its life cycle, virulence and pathogenesis must be investigated before prophylactic procedures can be properly designed. The development of effective control strategies for the disease has been limited due to a lack of knowledge about the biology, intracellular growth, transmission and virulence of the organism. Piscirickettsiosis has been difficult to control; the failure of antibiotic treatment is common, and currently used vaccines show variable long-term efficacy. This review summarizes the biology and characteristics of the bacterium, including its virulence; the infective strategy of P. salmonis for survival and evasion of the host immune response; the host immune response to invasion by this pathogen; and newly described features of the pathology, pathogenesis, epidemiology and transmission. Current approaches to the prevention of and treatment for piscirickettsiosis are discussed.
Collapse
Affiliation(s)
- M Rozas
- Faculty of Veterinary Sciences, Graduate School, Universidad Austral de Chile, Valdivia, Chile; Laboratory of Fish Pathology, Pathovet Ltd., Puerto Montt, Chile
| | | |
Collapse
|
30
|
Henríquez M, González E, Marshall SH, Henríquez V, Gómez FA, Martínez I, Altamirano C. A novel liquid medium for the efficient growth of the salmonid pathogen Piscirickettsia salmonis and optimization of culture conditions. PLoS One 2013; 8:e71830. [PMID: 24039723 PMCID: PMC3764132 DOI: 10.1371/journal.pone.0071830] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 07/03/2013] [Indexed: 11/18/2022] Open
Abstract
Piscirickettsia salmonis is the bacterium that causes Piscirickettsiosis, a systemic disease of salmonid fish responsible for significant economic losses within the aquaculture industry worldwide. The growth of the bacterium for vaccine formulation has been traditionally accomplished by infecting eukaryotic cell lines, a process that involves high production costs and is time-consuming. Recent research has demonstrated that it is possible to culture pure P. salmonis in a blood containing (cell-free) medium. In the present work we demonstrate the growth of P. salmonis in a liquid medium free from blood and serum components, thus establishing a novel and simplified bacteriological medium. Additionally, the new media reported provides improved growth conditions for P. salmonis, where biomass concentrations of approximately 800 mg cell dry weight L(-1) were obtained, about eight times higher than those reported for the blood containing medium. A 2- level full factorial design was employed to evaluate the significance of the main medium components on cell growth and an optimal temperature range of 23-27°C was determined for the microorganism to grow in the novel liquid media. Therefore, these results represent a breakthrough regarding P. salmonis research in order to optimize pure P. salmonis growth in liquid blood and serum free medium.
Collapse
Affiliation(s)
- Mirtha Henríquez
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Ernesto González
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Sergio H. Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
- NBC, Núcleo de Biotecnología Curauma, Curauma, Valparaíso, Chile
| | - Vitalia Henríquez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Fernando A. Gómez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Irene Martínez
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Claudia Altamirano
- Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
- CREAS CONICYT-REGIONAL, GORE Región de Valparaíso, Chile
- * E-mail:
| |
Collapse
|
31
|
Gómez FA, Tobar JA, Henríquez V, Sola M, Altamirano C, Marshall SH. Evidence of the presence of a functional Dot/Icm type IV-B secretion system in the fish bacterial pathogen Piscirickettsia salmonis. PLoS One 2013; 8:e54934. [PMID: 23383004 PMCID: PMC3557282 DOI: 10.1371/journal.pone.0054934] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 12/18/2012] [Indexed: 12/02/2022] Open
Abstract
Piscirickettsia salmonis is a fish bacterial pathogen that has severely challenged the sustainability of the Chilean salmon industry since its appearance in 1989. As this Gram-negative bacterium has been poorly characterized, relevant aspects of its life cycle, virulence and pathogenesis must be identified in order to properly design prophylactic procedures. This report provides evidence of the functional presence in P. salmonis of four genes homologous to those described for Dot/Icm Type IV Secretion Systems. The Dot/Icm System, the major virulence mechanism of phylogenetically related pathogens Legionella pneumophila and Coxiella burnetii, is responsible for their intracellular survival and multiplication, conditions that may also apply to P. salmonis. Our results demonstrate that the four P. salmonis dot/icm homologues (dotB, dotA, icmK and icmE) are expressed both during in vitro tissue culture cells infection and growing in cell-free media, suggestive of their putative constitutive expression. Additionally, as it happens in other referential bacterial systems, temporal acidification of cell-free media results in over expression of all four P. salmonis genes, a well-known strategy by which SSTIV-containing bacteria inhibit phagosome-lysosome fusion to survive. These findings are very important to understand the virulence mechanisms of P. salmonis in order to design new prophylactic alternatives to control the disease.
Collapse
Affiliation(s)
- Fernando A Gómez
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | | | | | | | | | | |
Collapse
|
32
|
Marshall SH, Gómez FA, Ramírez R, Nilo L, Henríquez V. Biofilm generation by Piscirickettsia salmonis under growth stress conditions: a putative in vivo survival/persistence strategy in marine environments. Res Microbiol 2012; 163:557-66. [DOI: 10.1016/j.resmic.2012.08.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 07/28/2012] [Indexed: 10/28/2022]
|
33
|
Xu T, Xie J, Li J, Luo M, Ye S, Wu X. Identification of expressed genes in cDNA library of hemocytes from the RLO-challenged oyster, Crassostrea ariakensis Gould with special functional implication of three complement-related fragments (CaC1q1, CaC1q2 and CaC3). FISH & SHELLFISH IMMUNOLOGY 2012; 32:1106-1116. [PMID: 22484279 DOI: 10.1016/j.fsi.2012.03.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Revised: 03/07/2012] [Accepted: 03/07/2012] [Indexed: 05/31/2023]
Abstract
A SMARTer™ cDNA library of hemocyte from Rickettsia-like organism (RLO) challenged oyster, Crassostrea ariakensis Gould was constructed. Random clones (400) were selected and single-pass sequenced, resulted in 200 unique sequences containing 96 known genes and 104 unknown genes. The 96 known genes were categorized into 11 groups based on their biological process. Furthermore, we identified and characterized three complement-related fragments (CaC1q1, CaC1q2 and CaC3). Tissue distribution analysis revealed that all of three fragments were ubiquitously expressed in all tissues studied including hemocyte, gills, mantle, digestive glands, gonads and adductor muscle, while the highest level was seen in the hemocyte. Temporal expression profile in the hemocyte monolayers reveled that the mRNA expression levels of three fragments presented huge increase after the RLO incubation at 3 h and 6 h in post-challenge, respectively. And the maximal expression levels at 3 h in post-challenge are about 256, 104 and 64 times higher than the values detected in the control of CaC1q1, CaC1q2 and CaC3, respectively.
Collapse
Affiliation(s)
- Ting Xu
- Laboratory of Marine Life Science and Technology, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, PR China
| | | | | | | | | | | |
Collapse
|
34
|
Yañez AJ, Valenzuela K, Silva H, Retamales J, Romero A, Enriquez R, Figueroa J, Claude A, Gonzalez J, Avendaño-Herrera R, Carcamo JG. Broth medium for the successful culture of the fish pathogen Piscirickettsia salmonis . DISEASES OF AQUATIC ORGANISMS 2012; 97:197-205. [PMID: 22422090 DOI: 10.3354/dao02403] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Piscirickettsiosis or salmonid rickettsial septicaemia (SRS) caused by Piscirickettsia salmonis constitutes one of the main problems in farmed salmonid and marine fishes. Since the first reports of the disease, it has been successfully isolated and maintained in eukaryotic cell--culture systems, but these systems are time-consuming, the media are costly, and eliminating heavily contaminated host cell debris is difficult. In this report, we describe a marine-based broth supplemented with L-cysteine, named AUSTRAL-SRS broth, that facilitates superior growth of P. salmonis strains. Strains reached an optical density of approximately 1.8 when absorbance was measured at 600 nm after 6 d incubation at 18°C. Several passages (n = 6) did not alter the culture kinetics. We report for the first time the purification of DNA, lipopolysaccharide (LPS) and whole membrane protein obtained from P. salmonis grown in this liquid medium, and thus provide a suitable platform to simplify the preparation of P. salmonis cells for genetic and serological studies. Moreover, the results of the cytopathic effect test showed that P. salmonis grown in AUSTRAL-SRS broth maintained their virulence properties, inducing apoptosis after 3 d. This makes the medium a good candidate for the successful growth of P. salmonis and an excellent basis for the development of low cost vaccines.
Collapse
Affiliation(s)
- A J Yañez
- Laboratorio de Enzimología, Instituto de Bioquímica, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Tacchi L, Bron JE, Taggart JB, Secombes CJ, Bickerdike R, Adler MA, Takle H, Martin SAM. Multiple tissue transcriptomic responses toPiscirickettsia salmonisin Atlantic salmon (Salmo salar). Physiol Genomics 2011; 43:1241-54. [DOI: 10.1152/physiolgenomics.00086.2011] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The bacterium Piscirickettsia salmonis is the etiological agent of salmonid rickettsial septicemia (SRS), a severe disease that causes major economic losses to the Atlantic salmon aquaculture industry every year. Little is known about the infective strategy of P. salmonis, which is able to infect, survive within, and replicate inside salmonid macrophages as an intracellular parasite. Similarly there is little knowledge concerning the fish host's response to invasion by this pathogen. We have examined the transcriptional response of postsmolt Atlantic salmon ( Salmo salar) to P. salmonis at 48 h following infection in three tissues, liver, head kidney, and muscle, using an Atlantic salmon oligonucleotide microarray (Salar_2, Agilent 4x44K). The infection led to a large alteration of transcriptional activity in all the tissues studied. In infected salmon 886, 207, and 153 transcripts were differentially expressed in liver, head kidney, and muscle, respectively. Assessment of enrichment for particular biological pathways by gene ontology analysis showed an upregulation of genes involved in oxidative and inflammatory responses in infected fish, indicative of the activation of the innate immune response. The downregulation of genes involved in the adaptive immune response, G protein signaling pathway, and apoptotic process in infected fish may be reflective of mechanisms used by P. salmonis to survive, replicate, and escape host defenses. There was also evidence of differential responses between studied tissues, with protein metabolism being decreased in muscle of infected fish and with a concomitant increase being shown in liver.
Collapse
Affiliation(s)
- Luca Tacchi
- Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen
| | - James E. Bron
- Institute of Aquaculture, University of Stirling, Stirling
| | | | - Christopher J. Secombes
- Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen
| | | | | | - Harald Takle
- Nofima, Aas, Norway; and
- AVS Chile, Puerto Varas, Chile
| | - Samuel A. M. Martin
- Institute of Biological and Environmental Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen
| |
Collapse
|
36
|
Ferrantini F, Fokin SI, Modeo L, Andreoli I, Dini F, Görtz HD, Verni F, Petroni G. "Candidatus Cryptoprodotis polytropus," a novel Rickettsia-like organism in the ciliated protist Pseudomicrothorax dubius (Ciliophora, Nassophorea). J Eukaryot Microbiol 2011; 56:119-29. [PMID: 19457052 DOI: 10.1111/j.1550-7408.2008.00377.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Rickettsia-like organisms (RLO) are obligate, often highly fastidious, intracellular bacterial parasites associated with a variety of vertebrate and invertebrate hosts. Despite their importance as causative agents of severe mortality outbreaks in farmed aquatic species, little is known about their life cycle and their host range. The present work reports the characterization of "Candidatus Cryptoprodotis polytropus," a novel Rickettsia-like bacterium associated with the common ciliate species Pseudomicrothorax dubius by means of the "Full-Cycle rRNA Approach" and ultrastructural observations. The morphological description by in vivo and scanning electron microscopy and the 18S rRNA gene sequence of the host species is provided as well. Phylogenetic analysis based on the 16S rRNA gene supports the inclusion of "Candidatus Cryptoprodotis polytropus" within the family Rickettsiaceae (cl. Alphaproteobacteria) together with the genera Rickettsia and Orientia. Observations on natural ciliate populations account for the occasional nature of this likely parasitic association. The presence of a previously unknown RLO in ciliates sheds a new light on the possible role of protists as transient hosts, vectors or natural reservoir for some economically important pathogens.
Collapse
Affiliation(s)
- Filippo Ferrantini
- Department of Biology, Protistology and Zoology Unit, University of Pisa, Via A. Volta 4/6, I-56126 Pisa, Italy
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Colquhoun DJ, Duodu S. Francisella infections in farmed and wild aquatic organisms. Vet Res 2011; 42:47. [PMID: 21385413 PMCID: PMC3060124 DOI: 10.1186/1297-9716-42-47] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Accepted: 03/08/2011] [Indexed: 01/08/2023] Open
Abstract
Over the last 10 years or so, infections caused by bacteria belonging to a particular branch of the genus Francisella have become increasingly recognised in farmed fish and molluscs worldwide. While the increasing incidence of diagnoses may in part be due to the development and widespread availability of molecular detection techniques, the domestication of new organisms has undoubtedly instigated emergence of clinical disease in some species. Francisellosis in fish develops in a similar fashion independent of host species and is commonly characterised by the presence of multi-organ granuloma and high morbidity, with varying associated mortality levels. A number of fish species are affected including Atlantic cod, Gadus morhua; tilapia, Oreochromis sp.; Atlantic salmon, Salmo salar; hybrid striped bass, Morone chrysops × M. saxatilis and three-lined grunt, Parapristipoma trilinineatum. The disease is highly infectious and often prevalent in affected stocks. Most, if not all strains isolated from teleost fish belong to either F. noatunensis subsp. orientalis in warm water fish species or Francisella noatunensis subsp. noatunensis in coldwater fish species. The disease is quite readily diagnosed following histological examination and identification of the aetiological bacterium by culture on cysteine rich media or PCR. The available evidence may indicate a degree of host specificity for the various Francisella strains, although this area requires further study. No effective vaccine is currently available. Investigation of the virulence mechanisms and host response shows similarity to those known from Francisella tularensis infection in mammals. However, no evidence exists for zoonotic potential amongst the fish pathogenic Francisella.
Collapse
Affiliation(s)
- Duncan J Colquhoun
- Section for Fish health, National Veterinary Institute, Postbox 750 sentrum, 0106 Oslo, Norway.
| | | |
Collapse
|
38
|
Gómez FA, Cárdenas C, Henríquez V, Marshall SH. Characterization of a functional toxin-antitoxin module in the genome of the fish pathogen Piscirickettsia salmonis. FEMS Microbiol Lett 2011; 317:83-92. [PMID: 21241361 DOI: 10.1111/j.1574-6968.2011.02218.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
This is the first report of a functional toxin-antitoxin (TA) locus in Piscirickettsia salmonis. The P. salmonis TA operon (ps-Tox-Antox) is an autonomous genetic unit containing two genes, a regulatory promoter site and an overlapping putative operator region. The ORFs consist of a toxic ps-Tox gene (P. salmonis toxin) and its upstream partner ps-Antox (P. salmonis antitoxin). The regulatory promoter site contains two inverted repeat motifs between the -10 and -35 regions, which may represent an overlapping operator site, known to mediate transcriptional auto-repression in most TA complexes. The Ps-Tox protein contains a PIN domain, normally found in prokaryote TA operons, especially those of the VapBC and ChpK families. The expression in Escherichia coli of the ps-Tox gene results in growth inhibition of the bacterial host confirming its toxicity, which is neutralized by coexpression of the ps-Antox gene. Additionally, ps-Tox is an endoribonuclease whose activity is inhibited by the antitoxin. The bioinformatic modelling of the two putative novel proteins from P. salmonis matches with their predicted functional activity and confirms that the active site of the Ps-Tox PIN domain is conserved.
Collapse
Affiliation(s)
- Fernando A Gómez
- Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | | | | | | |
Collapse
|
39
|
Abstract
Bacterial taxonomy has progressed from reliance on highly artificial culture-dependent techniques involving the study of phenotype (including morphological, biochemical and physiological data) to the modern applications of molecular biology, most recently 16S rRNA gene sequencing, which gives an insight into evolutionary pathways (= phylogenetics). The latter is applicable to culture-independent approaches, and has led directly to the recognition of new uncultured bacterial groups, i.e. "Candidatus", which have been associated as the cause of some fish diseases, including rainbow trout summer enteritic syndrome. One immediate benefit is that 16S rRNA gene sequencing has led to increased confidence in the accuracy of names allocated to bacterial pathogens. This is in marked contrast to the previous dominance of phenotyping, and identifications, which have been subsequently challenged in the light of 16S rRNA gene sequencing. To date, there has been some fluidity over the names of bacterial fish pathogens, with some, for example Vibrio anguillarum, being divided into two separate entities (V. anguillarum and V. ordalii). Others have been combined, for example V. carchariae, V. harveyi and V. trachuri as V. harveyi. Confusion may result with some organisms recognized by more than one name; V. anguillarum was reclassified as Beneckea and Listonella, with Vibrio and Listonella persisting in the scientific literature. Notwithstanding, modern methods have permitted real progress in the understanding of the taxonomic relationships of many bacterial fish pathogens.
Collapse
Affiliation(s)
- Brian Austin
- Institute of Aquaculture, Pathfoot Building, University of Stirling, Stirling FK9 4LA, Scotland, UK.
| |
Collapse
|
40
|
Olivares J, Marshall SH. Determination of minimal concentration of Piscirickettsia salmonis in water columns to establish a fallowing period in salmon farms. JOURNAL OF FISH DISEASES 2010; 33:261-266. [PMID: 20088869 DOI: 10.1111/j.1365-2761.2009.01119.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Abstract A highly sensitive real-time PCR procedure to detect and quantify the number of Pisciricketsia salmonis units in seawater samples from affected farm sites has been developed. The purpose was to determine a fallowing period that would allow safe restocking of the target farm with new fish. Bacterial load was determined in water samples by comparing the obtained amplification values against a standard curve generated by the amplification of known concentrations of the ITS-ribosomal component of P. salmonis DNA, cloned in a suitable vector. The standard curve was linear over the range of 10(1)-10(10) log units. Target samples were taken every 10 days over a 40-day period, at 5 m depth and at the surface. In a highly affected area of southern Chile, the number of bacterial units in farm water decreased to zero at day 50. Therefore, a fallowing period of 50 days post-removal of cages of affected fish appears to be appropriate before restocking. This procedure could be adapted to control disease problems because of other pathogens in fish farm waters.
Collapse
Affiliation(s)
- J Olivares
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
| | | |
Collapse
|
41
|
Zhu B, Wu X. Identification of outer membrane protein ompR from rickettsia-like organism and induction of immune response in Crassostrea ariakensis. Mol Immunol 2008; 45:3198-204. [DOI: 10.1016/j.molimm.2008.02.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Accepted: 02/29/2008] [Indexed: 12/01/2022]
|
42
|
Characterization of a novel and genetically different small infective variant of Piscirickettsia salmonis. Microb Pathog 2007; 44:370-8. [PMID: 18166333 DOI: 10.1016/j.micpath.2007.10.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2007] [Revised: 10/22/2007] [Accepted: 10/23/2007] [Indexed: 11/24/2022]
Abstract
We report a novel genetically different small infective variant of the fish pathogen Piscirickettsia salmonis (sP.s). sP.s variants were recovered both from ageing post-infected CHSE-214 culture cells as well as from naturally infected fish. The ITS region of sP.s variants, although sharing a common core sequence, is different from the ITS of the prototype strain LF-89 from which they originate. Thus, sP.s can be selectively amplified with sequence-specific discriminatory set of PCR primers. Transcriptionally, sP.s are fully active as shown by reverse transcription PCR analysis. Immunologically, sP.s is specifically recognized by antibodies against standard P. salmonis. Structurally, atomic force microscopy shows that sP.s. is well below (<0.2microm) the standard range size described for this pathogen (0.5-1.5microm). Functionally, although sP.s is infective their in vitro progeny is a hundred percent identical to the LF-89 prototype strain. In summary sP.s, represent selectable infective variants of the LF-89 strain and not new strains, probably resulting from a survival strategy of the bacteria in response to limiting growth conditions. In this frame, sP.s could be responsible of horizontal infection of fish in the field.
Collapse
|
43
|
Marshall SH, Conejeros P, Zahr M, Olivares J, Gómez F, Cataldo P, Henríquez V. Immunological characterization of a bacterial protein isolated from salmonid fish naturally infected with Piscirickettsia salmonis. Vaccine 2007; 25:2095-102. [PMID: 17250933 DOI: 10.1016/j.vaccine.2006.11.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2006] [Revised: 11/09/2006] [Accepted: 11/13/2006] [Indexed: 11/23/2022]
Abstract
The Salmon Rickettsia syndrome (SRS) remains a major infectious disease in the Chilean aquaculture. A limited number of Piscirickettsia salmonis proteins have been characterized so far for their use as potential candidates for vaccines studies. In this study, we identified and expressed a highly immunogenic protein of P. salmonis extracted by selective hydrophobicity from crude-cell macerates of naturally infected salmonid fish. One and two-D PAGE gels followed by Western blot analysis with a battery of polyclonal anti-P. salmonis antibodies have allowed the isolation of the target protein. Basic local alignment search (BLAST) done after partial sequencing of the pure protein identified it as a member of the heat-shock protein (HSP) family of prokaryotes. The protein, named ChaPs, was cloned as a single open reading frame encoding 545 amino acid residues with a predicted molecular mass of 57.3 kDa. The amplicon representing the entire novel gene was expressed in vitro in different heterologous systems: the PurePro Caulobacter crescentus expression system from where most of the characterization was attained, and also in the Escherichia coli BL-21 CodonPlus model for commercially potential purposes. The immunologic potential of ChaPs was determined with serum from naturally infected fish.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Bacterial/blood
- Bacterial Proteins/chemistry
- Bacterial Proteins/genetics
- Bacterial Proteins/immunology
- Bacterial Proteins/isolation & purification
- Blotting, Western
- Caulobacter/genetics
- Cloning, Molecular
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Electrophoresis, Gel, Two-Dimensional
- Electrophoresis, Polyacrylamide Gel
- Enzyme-Linked Immunosorbent Assay
- Fish Diseases/immunology
- Fish Diseases/microbiology
- Gene Expression
- Heat-Shock Proteins/immunology
- Heat-Shock Proteins/isolation & purification
- Molecular Sequence Data
- Molecular Weight
- Oncorhynchus kisutch
- Piscirickettsia/immunology
- Piscirickettsiaceae Infections/immunology
- Piscirickettsiaceae Infections/microbiology
- Piscirickettsiaceae Infections/veterinary
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
Collapse
Affiliation(s)
- Sergio H Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Facultad de Ciencias Básicas y Matemáticas, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2950, Valparaíso, Chile.
| | | | | | | | | | | | | |
Collapse
|
44
|
House ML, Hedrick RP, Winton JR, Fryer JL. An Isolate of Piscirickettsia salmonis from White Seabass is Fully Virulent for Coho Salmon. JOURNAL OF AQUATIC ANIMAL HEALTH 2006; 18:252-256. [PMID: 26599161 DOI: 10.1577/h05-056.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The virulence of the WSB-98 isolate of Piscirickettsia salmonis from white seabass Atractoscion nobilis was compared with that of the American Type Culture Collection type strain LF-89, which was originally isolated from coho salmon Oncorhynchus kisutch in Chile. In controlled laboratory challenges of juvenile coho salmon, the isolate from white seabass exhibited virulence that was equal to or greater than that of LF-89. The cumulative percent mortality (CPM) was similar between groups of coho salmon receiving an intraperitoneal injection of WSB-98 at 10(4.5) tissue culture infectious dose with 50% endpoint (TCID50)/fish (CPM = 98%) or an injection of LF-89 at 10(4.8) TCID50/fish (CPM = 95%). The mean day to death of 9.3 d for WSB-98 and 18.6 d for LF-89, however, differed significantly (P < 0.0001) between the two isolates. The virulence of an isolate of P. salmonis from white seabass for a salmonid species is consistent with the hypothesis that nonsalmonids can serve as natural marine hosts for the bacterium and potential sources for infection of salmonids.
Collapse
Affiliation(s)
- M L House
- a Department of Microbiology , Oregon State University , Corvallis , Oregon , 97331 , USA
| | - R P Hedrick
- b Department of Medicine and Epidemiology , School of Veterinary Medicine, University of California , Davis , California , 95616 , USA
| | - J R Winton
- c U.S. Geological Survey, Western Fisheries Research Center, Biological Resources Discipline , 6505 Northeast 65th Street , Seattle , Washington , 98115 , USA
| | - J L Fryer
- a Department of Microbiology , Oregon State University , Corvallis , Oregon , 97331 , USA
| |
Collapse
|