梁张岐,
李国鸿,
黄雅梦,
周攀,
张一诺,
袁青彬
南京工业大学环境科学与工程学院, 南京 211816

作者简介: 梁张岐(1998-),男,学士,研究方向为生物处理过程中抗性基因的检出、分布,E-mail:lzqfisher@126.com.

基金项目: 国家自然科学基金资助项目（51608260）；江苏省自然科学基金资助项目（BK20201367）


中图分类号: X171.5

Generation of Absorbed and Free Extracellular Antibiotic Resistance Genes during Biological Treatment Processes of Municipal Wastewater

Liang Zhangqi,
Li Guohong,
Huang Yameng,
Zhou Pan,
Zhang Yinuo,
Yuan Qingbin
College of Environmental Science and Technology, Nanjing Tech University, Nanjing 211816, China

CLC number: X171.5

-->

摘要
HTML全文
图(0)表(0)
参考文献(28)
相关文章
施引文献
资源附件(0)
访问统计

摘要:胞外抗生素抗性基因是抗性基因的重要存在形式，可能通过转化重新进入细胞表达抗药性。因此其具有严峻却隐蔽的健康风险，且不同形态胞外抗生素抗性基因的风险存在显著差异，然而当前针对胞外抗性基因风险的研究极为稀少。本研究以序批式活性污泥反应器（SBR）为例，考察了污水生物处理过程中结合型和游离型胞外抗性基因产生的时空特征，以及曝气强度和污泥负荷的影响。结果表明，SBR启动期2种胞外抗性基因均大量产生，且游离型胞外抗性基因的增加倍数和持续时间高于结合型；稳定运行后2种胞外抗性基因的丰度显著下降。从胞内外抗性基因的比重来看，好氧阶段以胞外抗性基因为主，且游离型胞外抗性基因比例达60%以上；厌氧阶段以胞内抗性基因为主，且结合型胞外抗性基因比例升高（7.5%~31.9%）；出水中游离型胞外抗性基因占据绝对优势，比例达66.5%~86.9%。曝气强度提高使2种胞外抗性基因丰度显著提高，但游离型胞外抗性基因提高程度（2.2倍~12.2倍）高于结合型（2.1倍~6.2倍）。污泥负荷提高同样导致2种胞外抗性基因丰度提高，但游离型胞外抗性基因提高程度（1.3倍~7.8倍）低于结合型（1.9倍~13.3倍）。研究表明，大量胞外抗性基因将在污水生物处理过程中产生，并随污水排放至环境中，是水环境中抗生素抗性基因（ARGs）的重要来源之一。
关键词: 结合型胞外抗生素抗性基因/
游离型胞外抗生素抗性基因/
曝气强度/
污泥负荷/
城市污水

Abstract:Extracellular antibiotic resistance genes (eARGs) are an important form of antibiotic resistance genes. eARGs may re-enter cells and express antibiotic resistance through transformation, thus imposing great but concealed health risks. Further, the risks of different forms of eARGs are significantly different. However, current studies on the risks of eARGs are extremely rare. This study investigated the spatiotemporal characteristics of absorbed eARGs (a-eARGs) and free eARGs (f-eARGs) during biological wastewater treatment processes by taking sequencing batch reactor (SBR) activated sludge process as an example, then the influence of aeration intensity and sludge loading rate were explored. Results showed that both types of eARGS were abundant during the start-up stage of SBR process, and the increase of f-eARGs were higher than a-eARGs in terms of content and period. The abundance of two forms of eARGs decreased significantly among steady operation stage. Concerning the proportion of eARGs and intracellular ARGs (iARGs), eARGs are dominant during the aeration stage and the proportion of feARGs was more than 60%. iARGs was dominant during the anaerobic stage, with the proportion of a-eARGs being increased to 7.5% ~ 31.9%. f-eARGs occupied in the effluent, with the proportion at 66.5% ~ 86.9%.The increase of aeration intensity significantly increased the abundance of two forms of eARGs, but the increase of feARGs (2.2 ~ 12.2 times) was higher than that of a-eARGs (2.1 ~ 6.2 times).The increase of sludge loading rate also resulted in the increase of two eARGs, but the increase in f-eARGs (1.3 ~ 7.8 times) was lower than that of the a-eARGs (1.9 ~ 13.3 times).This study indicates that abundant extracellular antibiotic resistance genes will be generated during the biological treatment processes of municipal wastewater and then discharged, which is an important ARGs sources of the aquatic environment.
Key words:absorbed eARGs/
free eARGs/
aeration intensity/
sludge loading rate/
municipal wastewater.

Li J N, Cheng W X, Xu L K, et al. Antibiotic-resistant genes and antibiotic-resistant bacteria in the effluent of urban residential areas, hospitals, and a municipal wastewater treatment plant system[J]. Environmental Science and Pollution Research, 2015, 22(6):4587-4596

罗义, 周启星. 抗生素抗性基因(ARGs)——一种新型环境污染物[J]. 环境科学学报, 2008, 28(8):1499-1505Luo Y, Zhou Q X. Antibiotic resistance genes (ARGs) as emerging pollutants[J]. Acta Scientiae Circumstantiae, 2008, 28(8):1499-1505(in Chinese)

de Leener E, Martel A, Decostere A, et al. Distribution of the erm (B) gene, tetracycline resistance genes, and Tn1545-like transposons in macrolide-and lincosamideresistant Enterococci from pigs and humans[J]. Microbial Drug Resistance, 2004, 10(4):341-345

Kim S R, Nonaka L, Suzuki S. Occurrence of tetracycline resistance genes tet(M) and tet(S) in bacteria from marine aquaculture sites[J]. FEMS Microbiology Letters, 2004, 237(1):147-156

吴楠, 杨静慧, 张伟玉, 等. 不同环境介质中抗生素耐药性的检测方法研究进展[J]. 微生物学通报, 2016, 43(12):2720-2729Wu N, Yang J H, Zhang W Y, et al. Progress in detection methods of antibiotic resistance in different environmental matrices[J]. Microbiology China, 2016, 43(12):2720-2729(in Chinese)

庄耀. 污水中抗生素抗性基因的深度净化技术研究[D]. 南京:南京大学, 2014:1-5 Zhuang Y. Research on purification technology of antibiotic resistance genes in municipal wastewater[D]. Nanjing:Nanjing University, 2014:1-5(in Chinese)

王丽梅, 罗义, 毛大庆, 等. 抗生素抗性基因在环境中的传播扩散及抗性研究方法[J]. 应用生态学报, 2010, 21(4):1063-1069Wang L M, Luo Y, Mao D Q, et al. Transport of antibiotic resistance genes in environment and detection methods of antibiotic resistance[J]. Chinese Journal of Applied Ecology, 2010, 21(4):1063-1069(in Chinese)

赵福正. 污水处理系统中ARGs、MGEs分布特征与菌群结构相关性研究[D]. 南京:南京大学, 2014:4-7 Zhao F Z. Correlations of distribution patterns of ARGs and MGEs with microbial communities in MSTPs revealed by high-throughput sequencing[D]. Nanjing:Nanjing University, 2014:4-7(in Chinese)

Yuan Q B, Guo M T, Yang J. Monitoring and assessing the impact of wastewater treatment on release of both antibiotic-resistant bacteria and their typical genes in a Chinese municipal wastewater treatment plant[J]. Environmental Science Processes & Impacts, 2014, 16(8):1930-1937

Yuan Q B, Huang Y M, Wu W B, et al. Redistribution of intracellular and extracellular free & adsorbed antibiotic resistance genes through a wastewater treatment plant by an enhanced extracellular DNA extraction method with magnetic beads[J]. Environment International, 2019, 131:104986

Zhang Y, Li A L, Dai T J, et al. Cell-free DNA:A neglected source for antibiotic resistance genes spreading from WWTPs[J]. Environmental Science & Technology, 2018, 52(1):248-257

Mao D Q, Luo Y, Mathieu J, et al. Persistence of extracellular DNA in river sediment facilitates antibiotic resistance gene propagation[J]. Environmental Science & Technology, 2014, 48(1):71-78

Zhang Y P, Snow D D, Parker D, et al. Intracellular and extracellular antimicrobial resistance genes in the sludge of livestock waste management structures[J]. Environmental Science & Technology, 2013, 47(18):10206-10213

Vlassov V V, Laktionov P P, Rykova E Y. Extracellular nucleic acids[J]. BioEssays, 2007, 29(7):654-667

Aardema B W, Lorenz M G, Krumbein W E. Protection of sediment-adsorbed transforming DNA against enzymatic inactivation[J]. Applied and Environmental Microbiology, 1983, 46(2):417-420

Lorenz M G, Wackernagel W. Adsorption of DNA to sand and variable degradation rates of adsorbed DNA[J]. Applied and Environmental Microbiology, 1987, 53(12):2948-2952

Hammond C M, Strømme C B, Huang H D, et al. Histone chaperone networks shaping chromatin function[J]. Nature Reviews Molecular Cell Biology, 2017, 18(3):141-158

Nagler M, Insam H, Pietramellara G, et al. Extracellular DNA in natural environments:Features, relevance and applications[J]. Applied Microbiology and Biotechnology, 2018, 102(15):6343-6356

Nielsen K M, Johnsen P J, Bensasson D, et al. Release and persistence of extracellular DNA in the environment[J]. Environmental Biosafety Research, 2007, 6(1-2):37-53

Wang R N, Zhang Y, Cao Z H, et al. Occurrence of super antibiotic resistance genes in the downstream of the Yangtze River in China:Prevalence and antibiotic resistance profiles[J]. Science of the Total Environment, 2019, 651:1946-1957

Zhang X X, Zhang T. Occurrence, abundance, and diversity of tetracycline resistance genes in 15 sewage treatment plants across China and other global locations[J]. Environmental Science & Technology, 2011, 45(7):2598-2604

Liu S S, Qu H M, Yang D, et al. Chlorine disinfection increases both intracellular and extracellular antibiotic resistance genes in a full-scale wastewater treatment plant[J]. Water Research, 2018, 136:131-136

Silva A F, Carvalho G, Soares R, et al. Step-by-step strategy for protein enrichment and proteome characterisation of extracellular polymeric substances in wastewater treatment systems[J]. Applied Microbiology and Biotechnology, 2012, 95(3):767-776

Ibáñez de Aldecoa A L, Zafra O, González-Pastor J E. Mechanisms and regulation of extracellular DNA release and its biological roles in microbial communities[J]. Frontiers in Microbiology, 2017, 8:1390

张晓春, 王金梅. 活性污泥法中影响微生物生长的关键因素的实验研究[C]. 长沙:中国化工学会, 2010:1-5 Zhang C X, Wang J M. Experimental research on the key factors affecting microbial growth in activated sludge process[C]. Changsha:Chemical Industry and Engineering Society of China, 2010:1-5(in Chinese)

赵曦. 好氧微生物净化污水的机理与实践[D]. 天津:天津大学, 2006:12-185

Hao H, Shi D Y, Yang D, et al. Profiling of intracellular and extracellular antibiotic resistance genes in tap water[J]. Journal of Hazardous Materials, 2019, 365:340-345

王冬, 王少坡, 周瑶, 等. 胞外聚合物在污水处理过程中的功能及其控制策略[J]. 工业水处理, 2019, 39(10):14-19Wang D, Wang S P, Zhou Y, et al. Function and control strategies of extracellular polymer substances in wastewater treatment process[J]. Industrial Water Treatment, 2019, 39(10):14-19(in Chinese)