摘要
      湖泊是水生环境中抗生素抗性基因（ARGs）和致病性耐药细菌的宿主和传播途径之一。先前的研究报告了ARGs在世界各地湖泊中的发生和分布；然而，很少有人研究环境中抗生素耐药性的生物地理学和多样性模式。为了填补这一空白，从全球分布的湖泊中收集了一组大规模的沉积物宏基因组数据，并使用基于宏基因组组装的分析进行了全面表征，旨在从全球角度揭示湖泊生态系统中ARGs的生物地理学和多样性模式。我们的分析表明，在全球湖泊沉积物中发现了丰富多样的ARGs，包括一组新出现的ARG，如mcr型和耐碳青霉烯类肠杆菌科相关基因。大多数已鉴定的ARGs通常与常用抗生素有关，这表明抗生素消费量的增加对耐药流行率的作用。从空间上看，ARG的组成和多样性在不同地理距离上有所不同，并表现出尺度依赖的距离衰减关系。值得注意的是，ARGs的组成在很大程度上由细菌群落结构决定，其多样性由随机过程（~48%）和确定性过程（~52%）共同决定。研究结果为更好地理解湖泊生态系统中ARGs的生态机制提供了宝贵的见解，并对预防和控制耐药风险具有重要意义。
Abstract
Lakes act as one of the reservoirs and dispersal routes of antibiotic resistance genes (ARGs) and pathogenic resistant bacteria in aquatic environments. Previous studies reported the occurrence and distribution of ARGs in lakes worldwide; however, few investigated the biogeography and diversity patterns of antibiotic resistome in the environment. To fill this gap, a large-scale data set of sediment metagenomes was collected from globally distributed lakes and characterized comprehensively using metagenomic assembly-based analysis, aiming to shed light on the biogeography and diversity patterns of ARGs in lake ecosystems from a global perspective. Our analyses showed that abundant and diverse ARGs were found in the global lake sediments, including a set of emerging ARGs such as mcr-type and carbapenem-resistant Enterobacteriaceae related genes. Most of the identified ARGs were generally associated with the commonly used antibiotics, suggesting the role of increasing antibiotic consumptions on the resistome prevalence. Spatially, the composition and diversity of ARGs varied across geographical distances and exhibited a scale-dependent distance-decay relationship. Notably, the composition of ARGs was largely shaped by bacterial community structure, and their diversities were co-governed by stochastic process (∼48%) and deterministic process (∼52%). Findings provide a valuable insight to better understand ecological mechanisms of ARGs in lake ecosystems and have important implication for the prevention and control of resistome risk.

https://www.sciencedirect.com/science/article/abs/pii/S1001074222003333