{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T10:33:13Z","timestamp":1785407593922,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T00:00:00Z","timestamp":1784073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100009465","name":"CORFO","doi-asserted-by":"publisher","award":["PI-4467"],"award-info":[{"award-number":["PI-4467"]}],"id":[{"id":"10.13039\/100009465","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"Agencia Nacional de Investigaci\u00f3n y Desarrollo","doi-asserted-by":"publisher","award":["21212273"],"award-info":[{"award-number":["21212273"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"Agencia Nacional de Investigaci\u00f3n y Desarrollo","doi-asserted-by":"publisher","award":["2121395"],"award-info":[{"award-number":["2121395"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002848","name":"Agencia Nacional de Investigaci\u00f3n y Desarrollo","doi-asserted-by":"publisher","award":["ACT240045"],"award-info":[{"award-number":["ACT240045"]}],"id":[{"id":"10.13039\/501100002848","id-type":"DOI","asserted-by":"publisher"}]},{"award":["21212273"],"award-info":[{"award-number":["21212273"]}],"id":[{"id":"https:\/\/ror.org\/02ap3w078","id-type":"ROR","asserted-by":"publisher"}]},{"award":["2121395"],"award-info":[{"award-number":["2121395"]}],"id":[{"id":"https:\/\/ror.org\/02ap3w078","id-type":"ROR","asserted-by":"publisher"}]},{"award":["ACT240045"],"award-info":[{"award-number":["ACT240045"]}],"id":[{"id":"https:\/\/ror.org\/02ap3w078","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Tenacibaculum maritimum is a major etiological agent of tenacibaculosis in marine fish and represents an increasing concern for Chilean salmon aquaculture; however, updated information on the phenotypic and molecular diversity of circulating isolates is limited. This study characterized 40 isolates recovered from Atlantic salmon (Salmo salar), rainbow trout (Oncorhynchus mykiss), and red cusk eel (Genypterus chilensis) obtained from outbreaks between 2020 and 2024. Isolates were analyzed using biochemical and phenotypic assays, multiplex PCR targeting the O-antigen gene cluster (O-AGC), REP-PCR-based genetic fingerprinting, and experimental bath challenges in Atlantic salmon. Phenotypic characterization revealed species-consistent traits but variable gelatin and starch hydrolysis and differences in seawater tolerance. O-AGC typing identified four molecular serotypes (1-0, 3-1, 3-2, and 4-0), with serotypes 1-0 and 3-2 detected for the first time in Chilean salmonids. Genetic fingerprinting distinguished previously described profiles and two novel REP patterns (REP6 and REP7), indicating additional genomic heterogeneity within dominant serotypes. Virulence assays showed cumulative mortality ranging from 0% to 100%, with serotype 3-1 isolates generally associated with higher mortality and serotype 4-0 displaying broad intra-serotype variability. These findings document substantial phenotypic, antigenic, and genetic diversity among Chilean T. maritimum isolates and provide epidemiologically relevant information for disease surveillance and vaccine design in salmon aquaculture.<\/jats:p>","DOI":"10.3390\/pathogens15070744","type":"journal-article","created":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T08:08:34Z","timestamp":1784189314000},"page":"744","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Phenotypic, Genetic, and Virulence Characterization of Tenacibaculum maritimum Isolates Recovered from Salmonid Outbreaks in Chile"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2933-2901","authenticated-orcid":false,"given":"Sara","family":"Valdes","sequence":"first","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"},{"name":"Biotechnology and Biopharmaceutical Laboratory, Pathophysiology Department, School of Biological Sciences, Universidad de Concepci\u00f3n, Concepcion 4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jos\u00e9 Miguel","family":"Saavedra","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenia","family":"Jerez","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elida","family":"Lebtun","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roxana","family":"Vargas","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pabla","family":"Barra","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9879-7710","authenticated-orcid":false,"given":"Jorge R.","family":"Toledo","sequence":"additional","affiliation":[{"name":"Biotechnology and Biopharmaceutical Laboratory, Pathophysiology Department, School of Biological Sciences, Universidad de Concepci\u00f3n, Concepcion 4070386, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9614-2393","authenticated-orcid":false,"given":"Jaime","family":"Romero","sequence":"additional","affiliation":[{"name":"Laboratorio de Biotecnolog\u00eda de Alimentos, Instituto de Nutrici\u00f3n y Tecnolog\u00eda de los Alimentos (INTA), Universidad de Chile, El L\u00edbano 5524, Santiago 7830489, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Harold","family":"Oliva","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pedro","family":"Ilardi","sequence":"additional","affiliation":[{"name":"Farmacolog\u00eda en Aquacultura Veterinaria FAV S.A.L., Santiago 9020000, Chile"},{"name":"Cooperative Program for Aquaculture (Universidad de Chile, Universidad Cat\u00f3lica del Norte, Pontificia Universidad Cat\u00f3lica de Valpara\u00edso), Universidad de Chile, El L\u00edbano 5524, Santiago 7830489, Chile"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.aquaculture.2005.01.002","article-title":"A review of main bacterial fish diseases in mariculture","volume":"246","author":"Toranzo","year":"2005","journal-title":"Aquaculture"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"255","DOI":"10.3354\/dao071255","article-title":"Tenacibaculosis infection in marine fish caused by T. maritimum: A review","volume":"71","author":"Toranzo","year":"2006","journal-title":"Dis. 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