Jia Jia, Guan Yongjing, Li Xiangju, Fan Xiaoteng, Zhu Zeliang, Xing Haoran, Wang Zaizhao
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Environ Res. 2021 May;196:110913. doi: 10.1016/j.envres.2021.110913. Epub 2021 Feb 24.
Acinetobacter johnsonii is a potentially opportunistic pathogen widely distributed in nosocomial and natural environments, but little attention has been paid to this bacillus. Here A. johnsonii strains from Ba River with different pollution levels were isolated. In this study, we found that the increasing anthropogenic contaminants accounted for the emergence of multidrug-resistant (MDR) A. johnsonii strains. Correlation analysis results showed that the resistance phenotype of strains could be generated by co-selection of heavy metals or non-corresponding antibiotics. The whole genome sequence analysis showed that the relative heavy pollution of water selects strains containing more survival-relevant genes. We found that only some genes like bla were responsible for its corresponding resistance profile. Additionally, the tolerance profiles toward heavy metals also attribute to the expression of efflux pumps rather than corresponding resistance genes. In summary, our finding revealed that the resistance profiles of A. johnsonii could be generated by cross or co-selection of anthropogenic contaminants and mediated by efflux pumps instead of corresponding resistance determinants. Our study also has deep-sight into the adaptive preference of bacteria in natural environments, and contributes to surveillance studies and MDR- A. johnsonii monitoring worldwide.
琼氏不动杆菌是一种潜在的机会致病菌，广泛分布于医院和自然环境中，但这种杆菌很少受到关注。在这里，我们分离了来自灞河不同污染水平的琼氏不动杆菌菌株。在本研究中，我们发现人为污染物的增加是多重耐药琼氏不动杆菌菌株出现的原因。相关性分析结果表明，菌株的耐药表型可能是由重金属或不相应抗生素的共选择产生的。全基因组序列分析表明，水体的相对重污染选择了含有更多生存相关基因的菌株。我们发现只有一些基因（如bla）对其相应的耐药谱负责。此外，对重金属的耐受谱也归因于外排泵的表达，而不是相应的耐药基因。总之，我们的研究结果表明，琼氏不动杆菌的耐药谱可能是由人为污染物的交叉或共选择产生的，并由外排泵介导，而不是由相应的耐药决定因素介导。我们的研究还深入了解了细菌在自然环境中的适应性偏好，并有助于全球范围内的监测研究和多重耐药琼氏不动杆菌的监测。
