摘要

       研究了臭氧处理系统以分析其对临床相关抗生素抗性细菌 (ARB) 和抗生素抗性基因 (ARG) 的影响。使用 0.9 ± 0.1 g 臭氧/1 g DOC 的浓度来处理传统的澄清废水。 PCR、qPCR 分析、Illumina 16S 扩增子测序和 PCR-DGGE 揭示了机会细菌的多种耐药性和敏感性模式以及臭氧处理后某些 ARG 的积累。肠球菌的分子标记基因表明对臭氧高度敏感。尽管它们减少了近 99%，但在臭氧处理后它们仍然存在于细菌群中。与此相反，铜绿假单胞菌在臭氧处理后仅显示出轻微的丰度变化。这表明微生物应对臭氧杀菌作用的不同机制。研究的 ARG 表现出更加多样化的模式。臭氧处理后，红霉素抗性基因 (ermB) 降低了 2 个数量级，但同时，幸存的废水群体 (vanA、blaVIM) 中其他两种临床相关 ARG 的丰度增加。 PCR-DGGE 分析和 16S 扩增子测序证实了一个类似选择的过程，以及臭氧处理后重要废水群体内的大量多样性损失。特别是 PCR-DGGE 结果证明了臭氧处理后富含 GC 的细菌的存活。

       An ozone treatment system was investigated to analyze its impact on clinically relevant antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARGs). A concentration of 0.9 ± 0.1 g ozone per 1 g DOC was used to treat conventional clarified wastewater. PCR, qPCR analyses, Illumina 16S Amplicon Sequencing, and PCR-DGGE revealed diverse patterns of resistances and susceptibilities of opportunistic bacteria and accumulations of some ARGs after ozone treatment. Molecular marker genes for enterococci indicated a high susceptibility to ozone. Although they were reduced by almost 99%, they were still present in the bacterial population after ozone treatment. In contrast to this, Pseudomonas aeruginosa displayed only minor changes in abundance after ozone treatment. This indicated different mechanisms of microorganisms to cope with the bactericidal effects of ozone. The investigated ARGs demonstrated an even more diverse pattern. After ozone treatment, the erythromycin resistance gene (ermB) was reduced by 2 orders of magnitude, but simultaneously, the abundance of two other clinically relevant ARGs increased within the surviving wastewater population (vanA, blaVIM). PCR-DGGE analysis and 16S-Amplicon-Sequencing confirmed a selection-like process in combination with a substantial diversity loss within the vital wastewater population after ozone treatment. Especially the PCR-DGGE results demonstrated the survival of GC-rich bacteria after ozone treatment.

https://www.sciencedirect.com/science/article/abs/pii/S0048969716305782