https://phaidra.vetmeduni.ac.at/o:3718 A brain microbiome in salmonids at homeostasis Mani, Amir Amir Mani 0000-0003-4417-622X Henn, Cory Cory Henn 0000-0002-3585-4597 Couch, Claire Claire Couch 0000-0003-4983-3719 Patel, Sonal Sonal Patel 0000-0003-4107-0497 Lieke, Thora Thora Lieke 0000-0002-4345-1712 Chan, Justin T. H. Justin T. H. Chan 0000-0003-4271-0177 Korytar, Tomas Tomas Korytar 0000-0002-6913-0415 Salinas, Irene Irene Salinas 0000-0002-4802-6571 American Association for the Advancement of Science journal article open access eng Ectotherms have peculiar relationships with microorganisms. For instance, bacteria are recovered from the blood and internal organs of healthy teleosts. However, the presence of microbial communities in the healthy teleost brain has not been proposed. Here, we report a living bacterial community in the brain of healthy salmonids with bacterial loads comparable to those of the spleen and 1000-fold lower than in the gut. Brain bacterial communities share >50% of their diversity with gut and blood bacterial communities. Using culturomics, we obtained 54 bacterial isolates from the brains of healthy trout. Comparative genomics suggests that brain bacteria may have adaptations for niche colonization and polyamine biosynthesis. In a natural system, Chinook salmon brain microbiomes shift from juveniles to reproductively mature adults. Our study redefines the physiological relationships between the brain and bacteria in teleosts. This symbiosis may endow salmonids with a direct mechanism to sense and respond to environmental microbes. Animals Brain Microbiology Homeostasis Microbiota Salmonidae Microbiology RNA Ribosomal 16S Genetics Phylogeny Bacteria Classification Genetics Isolation & Purification http://creativecommons.org/licenses/by-nc/4.0/ https://phaidra.vetmeduni.ac.at/api/object/o:3718/download 10.1126/sciadv.ado0277 https://phaidra.vetmeduni.ac.at/o:605 application/pdf Science Advances issn:2375-2548 VoR Science Advances 10 38 10.43 MB 2024