MARBEC, Université de Montpellier, CNRS, Ifremer, IRD, Place Eugène Bataillon - Bat 24, 34095, Montpellier, France.
Institut Méditerranéen d'Océanologie (MIO), Aix-Marseille Université, Université de Toulon, CNRS, Campus Technologique Et Scientifique de Luminy, 163 avenue de Luminy - Bat. Méditerranée, 13288, Marseille, IRD, France.
Microb Ecol. 2023 Jul;86(1):742-755. doi: 10.1007/s00248-022-02096-4. Epub 2022 Aug 13.
Although tunas represent a significant part of the global fish economy and a major nutritional resource worldwide, their microbiome still remains poorly documented. Here, we conducted an analysis of the taxonomic composition of the bacterial communities inhabiting the gut, skin, and liver of two most consumed tropical tuna species (skipjack and yellowfin), from individuals caught in the Atlantic and Indian oceans. We hypothesized that each organ harbors a specific microbial assemblage whose composition might vary according to different biotic (sex, species) and/or abiotic (environmental) factors. Our results revealed that the composition of the tuna microbiome was totally independent of fish sex, regardless of the species and ocean considered. Instead, the main determinants of observed diversity were (i) tuna species for the gut and (ii) sampling site for the skin mucus layer and (iii) a combination of both parameters for the liver. Interestingly, 4.5% of all amplicon sequence variants (ASV) were shared by the three organs, highlighting the presence of a core-microbiota whose most abundant representatives belonged to the genera Mycoplasma, Cutibacterium, and Photobacterium. Our study also revealed the presence of a unique and diversified bacterial assemblage within the tuna liver, comprising a substantial proportion of potential histamine-producing bacteria, well known for their pathogenicity and their contribution to fish poisoning cases. These results indicate that this organ is an unexplored microbial niche whose role in the health of both the host and consumers remains to be elucidated.
虽然金枪鱼在全球鱼类经济中占有重要地位，是全球主要的营养资源之一，但它们的微生物组仍未得到充分记录。在这里，我们分析了栖息在大西洋和印度洋捕获的两种最受欢迎的热带金枪鱼（鲣鱼和黄鳍金枪鱼）的肠道、皮肤和肝脏中的细菌群落的分类组成。我们假设每个器官都拥有特定的微生物群落，其组成可能因不同的生物（性别、物种）和/或非生物（环境）因素而有所不同。我们的结果表明，金枪鱼微生物组的组成与鱼类的性别完全无关，无论考虑的是哪种物种和海洋。相反，观察到的多样性的主要决定因素是（i）金枪鱼物种对肠道，（ii）皮肤黏液层的采样地点和（iii）两者的组合对肝脏。有趣的是，三个器官共有的所有扩增子序列变异体（ASV）有 4.5%，这突出了核心微生物组的存在，其最丰富的代表属于支原体属、葡萄球菌属和发光杆菌属。我们的研究还揭示了金枪鱼肝脏内存在独特且多样化的细菌群落，其中包含大量潜在的产组胺细菌，这些细菌因其致病性及其对鱼类中毒事件的贡献而广为人知。这些结果表明，这个器官是一个未被探索的微生物生态位，其在宿主和消费者健康中的作用仍有待阐明。
