PDF(Pubmed)
Abstract：
Microbial communities inhabiting sedimentary environments in river source regions serve as pivotal indicators of pristine river ecosystems. While the correlation between antibiotic resistome and pathogenicity with core gut bacteria in humans is well established, there exists a significant knowledge gap concerning the interaction of antibiotic resistance genes (ARGs) and human pathogenic bacteria (HPB) with specific microbes in river source basins, often referred to as \"terrestrial gut\". Understanding the microbial composition, including bacteria and resident genetic elements such as ARGs, HPB, Mobile Genetic Elements (MGEs), and Virulence Factors (VFs), within natural habitats against the backdrop of global change, is imperative. To address this gap, an enrichment-based culturomics complementary along with metagenomics was conducted in this study to characterize the microbial biobank and provide preliminary ecological insights into profiling the dissemination of ARGs in the Lancang River Source Basin. Based on our findings, in the main stream of the Lancang River Source Basin, 674 strains of bacteria, comprising 540 strains under anaerobic conditions and 124 under aerobic conditions, were successfully isolated. Among these, 98 species were identified as known species, while 4 were potential novel species. Of these 98 species, 30 were HPB relevant to human health. Additionally, bacA and bacitracin emerged as the most abundant ARGs and antibiotics in this river, respectively. Furthermore, the risk assessment of ARGs predominantly indicated the lowest risk rank (Rank Ⅳ) in terms of endangering human health. In summary, enrichment-based culturomics proved effective in isolating rare and unknown bacteria, particularly under anaerobic conditions. The emergence of ARGs showed limited correlation with MGEs, indicating minimal threats to human health within the main stream of the Lancang River Source Basin.
摘要：
居住在河源地区沉积环境中的微生物群落是原始河流生态系统的关键指标。虽然抗生素耐药性与人类核心肠道细菌的致病性之间的相关性已经确立，关于抗生素抗性基因（ARGs）和人类致病菌（HPB）与河流源流域特定微生物的相互作用存在显著的知识差距，通常被称为“陆地肠道”。了解微生物组成，包括细菌和常驻遗传元素，如ARG，HPB,移动遗传元素（MGEs），和毒力因子（VFs），在全球变化背景下的自然栖息地内，势在必行。为了解决这个差距，在这项研究中，进行了基于富集的文化生物学与宏基因组学的互补研究，以表征微生物生物库，并为分析澜沧江源流域ARGs的传播提供初步的生态见解。根据我们的发现,在澜沧江源流域的干流中，674株细菌，在厌氧条件下包含540个菌株，在有氧条件下包含124个菌株，成功隔离。其中,98个物种被确定为已知物种，而4个是潜在的新物种。在这98个物种中，30是与人类健康相关的HPB。此外,bacA和杆菌肽是这条河中最丰富的ARGs和抗生素，分别。此外，ARGs的风险评估主要表明危害人类健康的风险等级最低（Ⅳ级）。总之,基于富集的培养物被证明可以有效地分离稀有和未知的细菌，特别是在厌氧条件下。ARGs的出现与MGE的相关性有限，表明澜沧江源流域干流对人类健康的威胁最小。
