Microbiota exposed to pollution provide insights into host physiology and ecosystem disruption. This study evaluated Enterococcus spp. tolerant to arsenic (As), copper (Cu), and mercury (Hg) from red-billed tropicbirds (Phaethon aethereus) and brown boobies (Sula leucogaster), which previously showed these metals in their blood and feathers, and their potential use as bioindicators of metal contamination. Enterococcus casseliflavus (47.9 %), E. faecalis (34.1 %), E. hirae (11.7 %), and E. faecium (5.3 %) were identified. Both seabird species had a high incidence of As-tolerant bacteria (84.0 %), with 40.4 % of these strains containing As efflux system genes (arsA_I and arsA_II). Cu efflux pump gene (tcrB) was detected in 30.9 % of strains, while Hg reductase genes (mer) were not found. As- and Cu-tolerance in enterococci observed in this study underlines their potential as bioindicators in metal-polluted marine environments. Further research may elucidate the role of these metal-tolerant enterococci in seabird gut and their adaptability to polluted environments.

中文翻译：

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从巴西阿布罗霍斯群岛海鸟中分离出的肠球菌的金属耐受性：评估其作为海洋污染生物指示剂的作用


暴露于污染的微生物群提供了对宿主生理学和生态系统破坏的见解。这项研究评估了肠球菌属。对来自红嘴热带鸟 (Phaethon aethereus) 和棕鲣鸟 (Sula leucogaster) 的砷 (As)、铜 (Cu) 和汞 (Hg) 具有耐受性，之前在它们的血液和羽毛中发现了这些金属，并且它们的潜在用途金属污染的生物指示剂。鉴定出卡氏肠球菌 (47.9%)、粪肠球菌 (34.1%)、希拉肠球菌 (11.7%) 和屎肠球菌 (5.3%)。两种海鸟均具有较高的耐砷细菌发生率（84.0%），其中40.4%的菌株含有砷外排系统基因（arsA_I和arsA_II）。 30.9%的菌株检测到铜外排泵基因（tcrB），而未发现汞还原酶基因（mer）。本研究中观察到的肠球菌对砷和铜的耐受性突显了它们作为金属污染海洋环境中生物指示剂的潜力。进一步的研究可能会阐明这些耐金属肠球菌在海鸟肠道中的作用及其对污染环境的适应性。