Exposure of marine fish to hydrocarbon compounds from crude oil can cause physiological and ecological alterations that can resulting in several cytotoxic, genotoxic, and teratogenic damages. One consequence of this exposure is the dysbiosis of the gut microbiota, where the normal bacterial composition is modified. Herein, we assessed the effect of the exposure to water accommodated fraction (WAF) of a light crude oil into the gut microbiota of a native species, the lined sole Achirus lineatus, a benthonic fish widely distributed in the Gulf of Mexico (GoM). We performed a chronic bioassay using two WAF concentrations (5 and 10% v/v), collecting lined sole entire gastrointestinal tracts for microbiota analyses at two timepoints, 14 and 28 days. Changes in the gut microbiota composition were determined by high throughput amplicon sequencing of the gene 16S rRNA. Diversity analyses showed that WAF exposure produced similar changes in the microbiota composition at both concentrations. Metagenomic functional prediction showed that these alterations could result in a shift in the gut redox status, towards a more anoxygenic environment. Enrichment of bacteria capable of use hydrocarbon as carbon source seems to be fast regardless time of exposure or WAF concentrations. Our results suggest that chronic WAF exposure can cause a dysbiosis in this benthic native species from the GoM.

将海水鱼类暴露于原油中的碳氢化合物会引起生理和生态方面的变化，可能导致多种细胞毒性，遗传毒性和致畸性损害。这种暴露的结果是肠道微生物群的营养不良，其中正常细菌的成分被改变。本文中，我们评估了将轻质原油的水分容纳部分（WAF）暴露于原生物种肠道内生菌群（衬里的唯一Achirus lineatus）的影响是在墨西哥湾（GoM）广泛分布的底栖鱼类。我们使用两种WAF浓度（5％和10％v / v）进行了慢性生物测定，在14和28天的两个时间点收集内衬的整个胃肠道进行微生物群分析。肠道菌群组成的变化通过基因16S rRNA的高通量扩增子测序来确定。多样性分析表明，在两种浓度下，WAF暴露都会使微生物群组成产生相似的变化。元基因组功能预测表明，这些改变可能导致肠道氧化还原状态向着更致氧的环境转移。能够将碳氢化合物用作碳源的细菌的富集似乎很快，无论暴露时间或WAF浓度如何。