Gradient elution program for PFOS-K analysis.

Perfluorooctane sulfonate (PFOS) is a prominent perfluorinated compound commonly found in the environment, known to pose various risks to human health. However, the removal of PFOS presents significant challenges, primarily due to the limited discovery of bacteria capable of effectively degrading PFOS. Moreover, single degradation bacteria often encounter obstacles in individual cultivation and the breakdown of complex pollutants. In contrast, microbial consortia have shown promise in pollutant degradation. This study employed a continuous enrichment method, combined with multiple co-metabolic substrates, to investigate a microbial consortium with the potential for PFOS degradation. By employing this methodology, we effectively identified a microbial consortium that demonstrated the capacity to reduce PFOS when exposed to an optimal concentration of methanol. The consortium predominantly comprised of Hyphomicrobium species (46.7%) along with unclassified microorganisms (53.0%). Over a duration of 20 days, the PFOS concentration exhibited a notable decrease of 56.7% in comparison to the initial level, while considering the exclusion of adsorption effects. Furthermore, by comparing the predicted metabolic pathways of the microbial consortium with the genome of a known chloromethane-degrading bacterium, Hyphomicrobium sp. MC1, using the KEGG database, we observed distinct variations in the metabolic pathways, suggesting the potential role of the unclassified microorganisms. These findings underscore the potential effectiveness of a "top-down" functional microbial screening approach in the degradation of stubborn pollutants.全氟辛烷磺酸（Perfluorooctane sulfonate, PFOS）是一类广泛分布于环境中的典型全氟化合物（perfluorinated compound），已知其对人体健康存在多种潜在危害。然而，PFOS的去除面临极大挑战，主要原因是能够高效降解PFOS的细菌菌株鲜有报道。此外，单一降解菌往往在纯培养过程以及复杂污染物的降解中遭遇瓶颈。与之相对，微生物群落（microbial consortia）在污染物降解领域已展现出良好的应用前景。 本研究采用连续富集法（continuous enrichment method），结合多种共代谢底物（co-metabolic substrates），筛选具有PFOS降解潜力的微生物菌群。通过该研究策略，我们成功获得一株可在最优甲醇浓度下实现PFOS降解的微生物群落。该菌群主要由生丝微菌属（Hyphomicrobium）物种（占比46.7%）以及未分类微生物（占比53.0%）组成。在20天的培养周期内，排除吸附作用的干扰后，PFOS浓度较初始水平显著降低56.7%。 借助KEGG数据库，将该微生物群落的预测代谢通路与已知降解氯甲烷的生丝微菌MC1（Hyphomicrobium sp. MC1）的基因组进行比对后，我们发现二者代谢通路存在显著差异，提示未分类微生物可能在PFOS降解过程中发挥潜在作用。 本研究结果证实了“自上而下”的功能微生物筛选策略在难降解污染物治理中的应用潜力。