Degradation of tetracycline antibiotics by Arthrobacter nicotianae OTC-16
Degradation of tetracycline antibiotics by Arthrobacter nicotianae OTC-16
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烟草节杆菌 OTC-16 降解四环素类抗生素
DOI：
10.1016/j.jhazmat.2020.123996
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发表时间：
2021-02-05
影响因子：
13.6
通讯作者：
Zhang, Xin
中科院分区：
文献类型：
--
作者：
Shi, Yanke;Lin, Hui;Zhang, Xin
微生物降解是防治抗生素污染的重要途径。烟草节杆菌OTC-16是一株新型四环素降解菌，能降解土霉素/四环素（OTC/泰特）。毒性评价结果表明，该菌能有效地将土霉素转化为副产物，对细菌和藻类指标的毒性较小。初步鉴定了土霉素的六种降解产物，并提出了一种潜在的生物转化途径，包括脱羰基，还原和脱水。在各种基质中进一步研究了用这种细菌去除TC的生物强化。在水性介质中，菌株OTC-16在20-35 ℃的温度范围、6.0-9.0的pH范围和25-150 mg L-1的OTC浓度范围内加速OTC去除。该菌株还能降低猪粪和鸡粪中土霉素和泰特的浓度，最大降幅达91.54%，并使土壤中土霉素的降解率提高8.22- 45.45%.这种细菌在碱性环境中促进OTC降解的独特优势得到了证明，它成功地与土著微生物群竞争，并大大降低了土壤中所研究的四环素抗性基因（tetB和tetW）的相对丰度。这项工作提供了对抗生素生物强化和新微生物来源的更好理解。
Microbial degradation is an important option for combating antibiotic pollution. Arthrobacter nicotianae OTC-16 was isolated as a novel tetracycline-degrading bacterium, which could degrade oxytetracycline/tetracycline (OTC/TET). Toxicity assessment indicated that this bacterium effectively converted OTC into byproducts with less toxicity to bacterial and algal indicators. Six degradation products of OTC were tentatively identified, and a potential biotransformation pathway was proposed that includes decarbonylation, reduction, and dehydration. Bioaugmentation of TC removal with this bacterium was further studied in various matrices. In aqueous media, strain OTC-16 accelerated OTC removal over a temperature range of 20-35 degrees C, pH range of 6.0-9.0, and OTC concentration range of 25-150 mg L-1. The strain also facilitated the decrease of OTC and TET concentrations in both swine and chicken manures, with a maximum decrease of 91.54%, and increased the degradation of OTC in soils by 8.22-45.45%. A unique advantage of this bacterium in promoting OTC degradation in alkaline environments was demonstrated, where it successfully competed with the indigenous microbiota and largely decreased the relative abundances of the studied tetracycline resistance genes (tetB and tetW) in soil. This work offers a better understanding of the antibiotic bioaugmentation and new microbial sources.