The coexistence of nitrate and antibiotics in wastewater is a common problem. The study aimed to explore the response of denitrifying community, denitrification genes and antibiotic resistance genes (ARGs) to oxytetracycline (OTC) stress in polycaprolactone (PCL) supported solid-phase denitrification (SPD) reactors. Complete nitrate reduction (greater than99%) was achieved in SPD system with OTC stress of 0, 0.05, 0.25 and 1 mg L-1 during three-month operation, while it significantly declined by about 5% at a further increased OTC level of 5 mg L-1. The efficient denitrification strongly related with a rich diversity of denitrifiers, while the abundances of which dramatically reduced as the OTC concentration reached ≥0.25 mg L-1, which caused significant decline of denitrification genes, especially for narH, narJ, narI nirD, nosZ, and norB. Tetracycline resistance genes were a major type of promoted ARGs by different OTC stress, mainly related with the increase of tet36, tetG, tetA, tetM and tetC.

中文翻译：

---

聚己内酯固相反硝化反应器中反硝化群落，反硝化基因和抗生素抗性基因对土霉素胁迫的响应。

废水中硝酸盐和抗生素的共存是一个普遍的问题。该研究旨在探讨聚己内酯（PCL）固相反硝化（SPD）反应器中反硝化群落，反硝化基因和抗生素抗性基因（ARG）对土霉素（OTC）胁迫的响应。在SPD系统中，三个月的手术期间OTC应力分别为0、0.05、0.25和1 mg L-1时，硝酸盐完全还原（大于99％），而OTC进一步升高5时，硝酸盐显着下降约5％。毫克L-1。有效的反硝化作用与反硝化作用的丰富性密切相关，而随着OTC浓度达到≥0.25 mg L-1时，反硝化作用的丰富度急剧下降，这导致反硝化作用基因的显着下降，尤其是对于narH，narJ，narI nirD，nosZ，和norB。