摘要
      海洋沿海娱乐水域的微生物群落已成为AMR基因（ARGs）的大型宿主，导致各种人畜共患、食源性和其他对各种抗生素表现出耐药性的感染的出现和传播。因此，为了更好地了解AMR（AMR）的进化趋势，确定ARGs组合及其在这些微生物群落中传播的机制和轨迹是非常必要的。在这项研究中，我们使用宏基因组学方法，在巴统市（乔治亚州）黑海沿岸地区的娱乐水域中筛选ARGs。此外，SplitsTree、RDP4和GARD的大量重组检测算法被应用于阐明ARGs的基因重组及其在各种海洋微生物群落中的传播轨迹。从上述海洋地点获得的海水样本的宏基因组学分析可以确定编码多药耐药外排转运蛋白的假定ARG，这些转运蛋白主要来自主要促进者和耐药结节分部超家族。SplitsTree（拟合度≥95.619；自举值≥95；Phi p≤0.0494）、RDP4（p≤0.0490）和GARD生成的数据不仅为这些ARG的属内重组，而且为它们在相当大和多样化的海洋环境微生物群落中的属间重组提供了强有力的统计证据。这些细菌包括人类致病性和非致病性物种，共同表现为弧菌属、气单胞菌属、聚球藻属、柠檬微球菌属、红细菌科、假交替单胞菌、交替红细菌属、红细胞杆菌属、交替红细胞菌属、玛丽文属、须怀水菌属和洛克坦菌属。强烈认为上述非致病细菌有助于ARGs在海洋生态系统中的传播。
Abstract
Microbial communities of marine coastal recreation waters have become large reservoirs of AMR genes (ARGs), contributing to the emergence and transmission of various zoonotic, foodborne and other infections that exhibit resistance to various antibiotics. Thus, it is highly imperative to determine ARGs assemblages as well as mechanisms and trajectories of their transmission across these microbial communities for our better understanding of the evolutionary trends of AMR (AMR). In this study, using metagenomics approaches, we screened for ARGs in recreation waters of the Black Sea coastal areas of the Batumi City (Georgia). Also, a large array of the recombination detection algorithms of the SplitsTree, RDP4, and GARD was applied to elucidate genetic recombination of ARGs and trajectories of their transmission across various marine microbial communities. The metagenomics analyses of sea water samples, obtained from across the above marine sites, could identify putative ARGs encoding for multidrug resistance efflux transporters mainly from the Major Facilitator and Resistance Nodulation Division superfamilies. The data, generated by SplitsTree (fit ≥95.619; bootstrap values ≥ 95; Phi p ≤ 0.0494), RDP4 (p ≤ 0.0490), and GARD, provided strong statistical evidence not only for intrageneric recombination of these ARGs, but also for their intergeneric recombination across fairly large and diverse microbial communities of marine environment. These bacteria included both human pathogenic and nonpathogenic species, exhibiting collectively the genera of Vibrio, Aeromonas, Synechococcus, Citromicrobium, Rhodobacteraceae, Pseudoalteromonas, Altererythrobacter, Erythrobacter, Altererythrobacter, Marivivens, Xuhuaishuia, and Loktanella. The above nonpathogenic bacteria are strongly suggested to contribute to ARGs transmission in marine ecosystems.

https://www.sciencedirect.com/science/article/abs/pii/S1874778721000829