摘要

      抗生素耐药性是一个迅速增长的全球卫生保健问题，并导致许多疾病和死亡。在噬菌体在自然环境中传播的作用尚未得到明确解决的情况下，细菌可以通过移动基因元件介导的水平转移获得抗药性基因（ARGs）。从亚基因组研究中，我们发现在前噬菌体中发现的精氨酸的平均比例（0-0.0028%）低于在游离病毒中发现的精氨酸的平均比例（0.001-0.1%）。来自猪肠道病毒的β-内酰胺酶，占预测基因的0.10%。总的来说，在环境中，与病毒相关的ARG分布与人类活动密切相关，并且观察到的低dN/dS比率主张对病毒所携带的ARG进行阴性选择。我们的网络方法表明，病毒与假定的病原体（肠杆菌和弧菌科）有关，被认为是ARG转移的关键载体，类似于质粒。因此，与细菌基因组相比，这些arg可以在更大的时间和空间尺度上传播，从而允许时间延迟的遗传交换。

       Antibiotic resistance is a rapidly growing health care problem globally and causes many illnesses and deaths. Bacteria can acquire antibiotic resistance genes (ARGs) by horizontal transfer mediated by mobile genetic elements, where the role of phages in their dissemination in natural environments has not yet been clearly resolved. From metagenomic studies, we showed that the mean proportion of predicted ARGs found in prophages (0-0.0028%) was lower than those present in the free viruses (0.001-0.1%). Beta-lactamase, from viruses in the swine gut, represented 0.10 % of the predicted genes. Overall, in the environment, the ARG distribution associated with viruses was strongly linked to human activity, and the low dN/dS ratio observed advocated for a negative selection of the ARGs harbored by the viruses. Our network approach showed that viruses were linked to putative pathogens (Enterobacterales and vibrionaceae) and were considered key vehicles in ARG transfer, similar to plasmids. Therefore, these ARGs could then be disseminated at larger temporal and spatial scales than those included in the bacterial genomes, allowing for time-delayed genetic exchanges.

       https://www.nature.com/articles/s41396-019-0478-9