摘要

       使用从序列读取档案 (SRA) 获得的 122 个水生宏基因组 DNA 数据集（92 个湖水和 30 个海水）进行了全球调查。抗生素抗性基因（ARGs）和金属抗性基因（MRGs）通过生物信息学分析从数据集序列中获得。湖泊样品中ARGs和MRGs的相对丰度在ND（未检测到）-1.34×100和1.22×10-3-1.98×10-1个拷贝/16S rRNA的范围内，高于海水样品中的丰度。在ARGs中，多药抗性基因和杆菌肽抗性基因在湖水和海水样品中均具有较高的相对丰度。多金属抗性基因、汞抗性基因和铜抗性基因对MRGs的相对丰度最大。丰度或 ARG 和 MRG 的香农多样性指数之间没有发现显着差异。主坐标分析和置换多元方差分析（PERMANOVA）检验表明，分层和地理对湖泊中ARGs和MRGs的组成有显着影响（p<0.05，PERMANOVA）。与深海和南极海水样品相比，沿海海水样品的 ARGs 和 MRGs 的相对丰度和香农指数显着更高（p<0.05，Kruskal-Wallis 单向方差分析），表明人类活动可能对 ARGs 施加更大的选择压力沿海地区的MRGs比深海和南极海水中的MRGs多。

       A global survey was performed with 122 aquatic metagenomic DNA datasets (92 lake water and 30 seawater) obtained from the Sequence Read Archive (SRA). Antibiotic resistance genes (ARGs) and metal resistance genes (MRGs) were derived from the dataset sequences via bioinformatic analysis. The relative abundances of ARGs and MRGs in lake samples were in the ranges ND (not detected)–1.34 × 100 and 1.22 × 10−3–1.98 × 10−1 copies per 16S rRNA, which were higher than those in seawater samples. Among ARGs, multidrug resistance genes and bacitracin resistance genes had high relative abundances in both lake and sea water samples. Multi-metal resistance genes, mercury resistance genes and copper resistance genes had the greatest relative abundance for MRGs. No significant difference was found between epilimnion and hypolimnion in abundance or the Shannon diversity index for ARGs and MRGs. Principal coordinates analysis and permutational multivariate analysis of variance (PERMANOVA) test showed that stratification and geography had significant influence on the composition of ARGs and MRGs in lakes (p < 0.05, PERMANOVA). Coastal seawater samples had significantly greater relative abundance and a higher Shannon index for both ARGs and MRGs than deep ocean and Antarctic seawater samples (p < 0.05, Kruskal-Wallis one-way ANOVA), suggesting that human activity may exert more selective pressure on ARGs and MRGs in coastal areas than those in deep ocean and Antarctic seawater.

https://www.sciencedirect.com/science/article/pii/S0160412018332161