المؤلفون: Morel-Letelier I; Eco-Evolutionary Interactions Group, Max Planck Institute for Marine Microbiology (MPIMM), Bremen, Germany., Yuen B; Eco-Evolutionary Interactions Group, Max Planck Institute for Marine Microbiology (MPIMM), Bremen, Germany., Kück AC; Eco-Evolutionary Interactions Group, Max Planck Institute for Marine Microbiology (MPIMM), Bremen, Germany., Camacho-García YE; Centro de Investigación en Ciencias del Mar y Limnología (CIMAR), Universidad de Costa Rica, San Pedro, San José, Costa Rica.; Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET), Universidad de Costa Rica, San Pedro, San José, Costa Rica.; Escuela de Biología, Universidad de Costa Rica, San Pedro, San José, Costa Rica., Petersen JM; Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria., Lara M; Diving Center Cuajiniquil, Provincia de Guanacaste, Cuajiniquil, Costa Rica., Leray M; Smithsonian Tropical Research Institute, Balboa, Ancon, Republic of Panamá., Eisen JA; Department of Evolution and Ecology, University of California, Davis, Davis, California, United States of America.; Department of Medical Microbiology and Immunology, University of California, Davis, Davis, California, United States of America., Osvatic JT; Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria.; Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria., Gros O; Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, Université des Antilles, Pointe-à-Pitre, France., Wilkins LGE; Eco-Evolutionary Interactions Group, Max Planck Institute for Marine Microbiology (MPIMM), Bremen, Germany.

المصدر: PLoS genetics [PLoS Genet] 2024 May 31; Vol. 20 (5), pp. e1011295. Date of Electronic Publication: 2024 May 31 (Print Publication: 2024).

نوع المنشور: Journal Article

بيانات الدورية: Publisher: Public Library of Science Country of Publication: United States NLM ID: 101239074 Publication Model: eCollection Cited Medium: Internet ISSN: 1553-7404 (Electronic) Linking ISSN: 15537390 NLM ISO Abbreviation: PLoS Genet Subsets: MEDLINE

مواضيع طبية MeSH: Symbiosis*/genetics , Phylogeny* , Nitrogen Fixation*/genetics , Nitrogen*/metabolism , Bivalvia*/microbiology , Bivalvia*/genetics , Gene Transfer, Horizontal*, Animals ; Bacteria/genetics ; Bacteria/classification ; Bacteria/metabolism ; Adaptation, Physiological/genetics ; Genome, Bacterial ; Caribbean Region ; Panama

مستخلص: Bacterial symbionts, with their shorter generation times and capacity for horizontal gene transfer (HGT), play a critical role in allowing marine organisms to cope with environmental change. The closure of the Isthmus of Panama created distinct environmental conditions in the Tropical Eastern Pacific (TEP) and Caribbean, offering a "natural experiment" for studying how closely related animals evolve and adapt under environmental change. However, the role of bacterial symbionts in this process is often overlooked. We sequenced the genomes of endosymbiotic bacteria in two sets of sister species of chemosymbiotic bivalves from the genera Codakia and Ctena (family Lucinidae) collected on either side of the Isthmus, to investigate how differing environmental conditions have influenced the selection of symbionts and their metabolic capabilities. The lucinid sister species hosted different Candidatus Thiodiazotropha symbionts and only those from the Caribbean had the genetic potential for nitrogen fixation, while those from the TEP did not. Interestingly, this nitrogen-fixing ability did not correspond to symbiont phylogeny, suggesting convergent evolution of nitrogen fixation potential under nutrient-poor conditions. Reconstructing the evolutionary history of the nifHDKT operon by including other lucinid symbiont genomes from around the world further revealed that the last common ancestor (LCA) of Ca. Thiodiazotropha lacked nif genes, and populations in oligotrophic habitats later re-acquired the nif operon through HGT from the Sedimenticola symbiont lineage. Our study suggests that HGT of the nif operon has facilitated niche diversification of the globally distributed Ca. Thiodiazotropha endolucinida species clade. It highlights the importance of nitrogen availability in driving the ecological diversification of chemosynthetic symbiont species and the role that bacterial symbionts may play in the adaptation of marine organisms to changing environmental conditions.
Competing Interests: The authors have declared that no competing interests exist.
(Copyright: © 2024 Morel-Letelier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)