作为一种新兴污染物，抗生素四环素 (TC) 在废水和活性污泥中不断被检测到。生物降解是消除TC污染的潜在关键途径。然而，目前分离出的有效TC降解细菌很少，并且仍然缺乏对TC降解分子机制的全面了解。在这项研究中，一种新型的 TC 降解细菌被命名为鞘氨醇杆菌sp。WM1，已成功从活性污泥中分离出来。在共代谢条件下，菌株WM1在1天内降解50 mg/L TC表现出卓越的性能。对 WM1 菌株的基因组分析揭示了三个功能性tetX基因的存在。转录组分析揭示了复杂的分子机制，强调了上调跨膜传输和加速电子传输在促进 TC 降解中的作用。蛋白质组学证实了参与细胞生物合成/代谢和核糖体过程的蛋白质的上调。至关重要的是，tetX基因编码蛋白表现出显着的上调，表明其在 TC 降解中的作用。tetX基因的异源表达导致TC在24小时内从最初的51.9 mg/L消散至4.2 mg/L。降解途径包括 TC 羟基化，转化为 TP461 和随后的代谢物，从而有效地耗尽 TC 的抑制活性。值得注意的是，菌株 WM1 中的tetX基因显示水平基因转移的潜力有限。总的来说，WM1 菌株强大的 TC 降解能力预示着增强 TC 清理策略的前景。

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As an emerging pollutant, the antibiotic tetracycline (TC) has been consistently detected in wastewater and activated sludge. Biodegradation represents a potentially crucial pathway to dissipate TC contamination. However, few efficient TC-degrading bacteria have been isolated and a comprehensive understanding of the molecular mechanisms underlying TC degradation is still lacking. In this study, a novel TC-degrading bacterium, designated as Sphingobacterium sp. WM1, was successfully isolated from activated sludge. Strain WM1 exhibited a remarkable performance in degrading 50 mg/L TC within 1 day under co-metabolic conditions. Genomic analysis of the strain WM1 unveiled the presence of three functional tetX genes. Unraveling the complex molecular mechanisms, transcriptome analysis highlighted the role of upregulated transmembrane transport and accelerated electron transport in facilitating TC degradation. Proteomics confirmed the up-regulation of proteins involved in cellular biosynthesis/metabolism and ribosomal processes. Crucially, the tetX gene-encoding protein showed a significant upregulation, indicating its role in TC degradation. Heterologous expression of the tetX gene resulted in TC dissipation from an initial 51.9 mg/L to 4.2 mg/L within 24 h. The degradation pathway encompassed TC hydroxylation, transforming into TP461 and subsequent metabolites, which effectively depleted TC's inhibitory activity. Notably, the tetX genes in strain WM1 showed limited potential for horizontal gene transfer. Collectively, strain WM1′s potent TC degradation capacity signals a promise for enhancing TC clean-up strategies.