{"paper_id":"086e40e3-91ec-4010-a751-0c33f252163c","body_text":"Deep Metagenomics Uncovers Functional Adaptations and Pathogenic Risks in the Gut Microbiome of Antarctic Fur Seals (Arctocephalus gazella) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Deep Metagenomics Uncovers Functional Adaptations and Pathogenic Risks in the Gut Microbiome of Antarctic Fur Seals (Arctocephalus gazella) Tingyi Lai, Yisi Liu, Zedong Duan, Shiyuan Su, Jin Zhang, Haitao Ding, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8441910/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 9 You are reading this latest preprint version Abstract The Antarctic fur seal (Arctocephalus gazella) plays a key role in the Antarctic marine ecosystem by regulating krill, fish, and cephalopod populations through selective foraging, promoting Southern Ocean productivity via excretion, and influencing coastal island ecosystems during breeding season. Despite the importance of the gut microbiota in reflecting diet, health, and environmental adaptation, the gut microbiome of the Antarctic fur seal remains underexplored. This study employed shotgun metagenomics and 16S rRNA amplicon sequencing to analyze the gut microbiota of Antarctic fur seals, using fresh fecal samples directly collected from four individuals at King George Island, Western Antarctica. Despite inter-individual variation, both approaches identified Bacillota as the dominant phylum but showed genus-level discrepancies, with Fusobacterium prevailing in metagenomes and Clostridium in 16S amplicons. Viral communities constituted up to 5.3% of the microbiome, including immunodeficiency-associated Lentivirus. Core microbiome analysis identified 31 (16S rRNA) and 1,522 (metagenomics) shared genera, with functional enrichment in carbohydrate, amino acid, and lipid metabolism pathways. Chitin-degrading enzymes, crucial for krill digestion, were ubiquitous. Additionally, a total of 16 antibiotic resistance gene types were detected, with bacitracin, polymyxin, and multidrug resistance dominating the resistome. Metagenome-assembled genomes revealed phylogenetic diversity, with Angelakisella, Massillimalia and Faecousia encoding chitinase, while Helicobacter, especially abundant in S62, implied pathogenic potential. These findings provide an in-depth elucidation of the microbial community composition, functional potential, and ecological adaptation of seal gut microbiota, also offering valuable scientific data and methodological insights for the conservation of polar marine mammals. Arctocephalus gazella shotgun metagenomics gut microbiome chitin-degradation antimicrobial resistance pathogenic risk Full Text Additional Declarations No competing interests reported. Supplementary Files TableS3.Taxonomiccompositionofbacterialcommunitiesatthephylumlevelbasedonmetagenomicdata.xlsx TableS1.Taxonomiccompositionatthegenuslevelbasedon16SrRNAamplicondata.xlsx TableS5.Sharedgenerabetweentwosequencingmethods.xlsx TableS4.Taxonomiccompositionofbacterialcommunitiesatthegenuslevelbasedonmetagenomicdata.xlsx Supplementarymaterial.docx Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 28 Apr, 2026 Reviews received at journal 27 Apr, 2026 Reviewers agreed at journal 27 Apr, 2026 Reviews received at journal 17 Mar, 2026 Reviewers agreed at journal 02 Mar, 2026 Reviewers invited by journal 02 Mar, 2026 Editor assigned by journal 14 Jan, 2026 Submission checks completed at journal 13 Jan, 2026 First submitted to journal 12 Jan, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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