摘要
      近年来，在海洋环境中，微生物抗生素耐药性基因（ARG）亚型，特别是新型β-内酰胺酶的出现和数量不断增加，引起了人们的广泛关注。使用新开发的工具更新的数据库为获得更全面的ARG配置文件以及携带ARG的主机提供了新的机会。然而，与人类相关的海洋水产养殖环境中的ARGs，例如在中国，在很大程度上仍然未知。利用宏基因组数据，我们揭示了全年大量的多药耐药性、β-内酰胺酶和氨基糖苷类基因。因此，阿尔法和伽马蛋白细菌被分配给大多数携带β-内酰胺酶的宿主。从元基因组组装的基因组中，仅在一个未分类的分枝杆菌属中观察到三种blaF样β-内酰胺酶（与偶然分枝杆菌（blaF）的β-内胺酶的同源性为91.7–94.7%）。值得注意的是，在γ-变形杆菌中发现了其他新的β-内酰胺酶，即VMB-1样（n=3）（与金属-β-内啡肽弧菌1（VMB-1）具有58.5-67.4%的同一性）。此外，175种耐多药生物至少具有3种ARG亚型，其中7个潜在致病属（n=17）被分配给γ-变形杆菌。这些结果，加上高危ARGs（如tetM、dfrA14和dfrA17），为中国沿海水产养殖中的ARGs提供了宿主和新的β-内酰胺酶。
Abstract
In marine environments, increasing occurrence and numbers of microbial Antibiotic Resistance Gene (ARG) subtypes, especially of new beta-lactamases, have received lots of attention in recent years. Updated databases with novel developed tools provide new opportunities to obtain more comprehensive ARG profiles as well as ARG-carrying hosts. Yet, ARGs in human-associated marine aquaculture environments, e.g. in China, remains largely unknown. Using metagenomic data, we revealed high numbers of Multi-drug Resistance, beta-lactamase and aminoglycoside genes throughout the year. Thereby, Alpha- and Gamma-proteobacteria were assigned to the majority of beta-lactamase-carrying hosts. From Metagenome-assembled genomes, three blaF-like beta-lactamases (91.7–94.7% identity with beta-lactamase from Mycobacterium fortuitum (blaF)) were exclusively observed in an unclassified Mycobacterium genus. Notably, other new beta-lactamases, VMB-1-like (n = 3) (58.5–67.4% identity to Vibrio metallo-beta-lactamase 1 (VMB-1)), were found in Gammaproteobacteria. Additionally, 175 Multi-drug Resistant Organisms possessed at least 3 ARG subtypes, and seven of the potentially pathogenic genera (n = 17) were assigned to Gammaproteobacteria. These results, together with high-risk ARGs (e.g. tetM, dfrA14 and dfrA17), provide hosts and new beta-lactamases of ARGs in Chinese coastal aquaculture.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722028819