摘要
      抗生素的广泛使用导致大量抗生素进入环境，微生物对环境产生了耐药性。近年来，随着高原地区人类活动的加剧，抗生素抗性基因（ARGs）在高原湿地的发生和迁移引起了人们的关注。在这里，我们选择了位于云贵高原的草海国家湿地公园作为我们的研究区域。分析了公园河流上游（泉眼附近的原始栖息地）和下游（居民污水排放口）沉积物中四环素类、磺酰胺类、喹诺酮类和大环内酯类的含量。其中四环素类抗生素的检测含量为103.65-2185μg·kg-1，为最高的抗生素检测含量。为了进一步研究四环素抗性基因的发生特征和影响因素，通过相关性分析和网络分析揭示了环境因素、细菌群落结构和致病菌对人类活动影响下四环素ARGs的影响。结果表明，在上游和下游沉积物中共检测到15个四环素抗性基因。其中，上游检测到tetPA、tetD和tetPB等7个抗性基因，下游检测到tetPA、tetE、tetM和tetX等13个抗性基因。下游8个新抗性基因的丰度占下游基因的43.44%。类四环素抗生素和土壤理化指标（即有效磷、总有机碳、硝态氮和总磷）是影响四环素ARGs分布的主要环境因素。此外，在上游和下游沉积物中检测到的细菌属于64个细菌门，其中变形菌门、厚壁菌门和拟杆菌门是影响四环素ARGs丰度的主要门；同时，在上下游沉积物中检测到27种致病菌。网络分析显示，8个新的抗性基因与下游地区病原体之间的相关性占网络连通性的70%，单核细胞增多性李斯特菌、粪肠球菌和硫化拟杆菌被确定为四环素ARGs传播的潜在宿主。与原始栖息地相比，生活污水的排放引入了大量抗生素，也改变了河流湿地的微环境和微生物群落结构。此外，它增加了沉积物中ARGs的种类，促进了ARGs在微生物甚至病原体之间的传播。
Abstract 
The widespread use of antibiotics has led to a large number of antibiotics entering the environment, to which microorganisms have become resistant. In recent years, with the intensification of human activities in the plateau region, the occurrence and migration of antibiotic resistance genes (ARGs) in plateau wetlands have attracted considerable attention. Here, we selected the Caohai National Wetland Park, located in the Yunnan-Guizhou Plateau, as our study area. The contents of tetracyclines, sulfonamides, quinolones, and macrolides in sediments from the upstream (the pristine habitat near the spring eye) and downstream (the sewage discharge outlet of residents) areas of the river in the park were analyzed. Among them, the detection content of tetracycline antibiotics was 103.65-2185 μg·kg-1, which was the highest antibiotic detection content. To further investigate the occurrence characteristics and influencing factors of tetracycline resistance genes, the influence of environmental factors, bacterial community structure, and pathogenic bacteria on tetracycline ARGs under the influence of human activities were revealed via correlation analysis and network analysis. The results showed that a total of 15 tetracycline resistance genes were detected in the upstream and downstream sediments. Among them, seven resistance genes including tetPA, tetD, and tetPB were detected in the upstream, and 13 resistance genes such as tetPA, tetE, tetM, and tetX were detected in the downstream. The abundance of eight new resistance genes in the downstream accounted for 43.44% of the downstream genes. The tetracycline-like antibiotics and soil physicochemical indicators (i.e., available phosphorus, total organic carbon, nitrate nitrogen, and total phosphorus) were the main environmental factors affecting the distribution of tetracycline ARGs. Additionally, the bacteria detected in the upstream and downstream sediments belonged to 64 bacterial phyla, among which Proteobacteria, Firmicutes, and Bacteroidota were the main phyla affecting the abundance of tetracycline ARGs; meanwhile, 27 pathogenic bacteria were detected in the upstream and downstream sediments. Network analysis showed that the correlation between the eight new resistance genes and pathogens in the downstream area accounted for 70% of the network connectivity, and Listeria monocytogenes, Enterococcus faecalis, and Bacteroides vulgatus were identified as potential hosts for the transmission of tetracycline ARGs. Compared to the pristine habitat, the discharge of domestic sewage introduced large amounts of antibiotics and also changed the microenvironment and microbial community structure of the river wetland. Additionally, it increased the species of ARGs in sediments, which promoted the spread and transmission of ARGs among microorganisms and even pathogens.

https://europepmc.org/article/med/36635805