Table_2_Insights into coastal microbial antibiotic resistome through a meta-transcriptomic approach in Yucatan.XLSX

Antibiotic resistance (AR) is one of the greatest human and clinical challenges associated with different pathogenic organisms. However, in recent years it has also become an environmental problem due to the widespread use of antibiotics in humans and livestock activities. The ability to resist antibiotics comes from antibiotic resistance genes (ARGs) and our understanding of their presence in coastal environments is still limited. Therefore, the objective of the present study was to explore the presence and possible differences in the microbial resistome of four sites from the Yucatan coast through the evaluation of the composition and abundance of ARGs using a high-throughput analysis of metatranscriptomic sequences. In total, 3,498 ARGs were uncovered, which participate in the resistance to tetracycline, macrolide, rifamycin, fluoroquinolone, phenicol, aminoglycoside, cephalosporin, and other antibiotics. The molecular mechanisms of these ARGs were mainly efflux pump, antibiotic target alteration and antibiotic target replacement. In the same way, ARGs were detected in the samples but showing dissimilar enrichment levels. With respect to the sampling sites, the ARGs were present in all the samples collected, either from preserved or contaminated areas. Importantly, sediments of the preserved area of Dzilam presented the second highest level of ARGs detected, probably as a consequence of the antibiotics dragged to the coast by submarine groundwater discharge. In general, the resistance to a single antibiotic was greater than multiresistance, both at the level of gene and organisms; and multiresistance in organisms is acquired mainly by recruiting different monoresistance genes. To our knowledge, this is the first study that describes and compares the resistome of different samples of the Yucatan coast. This study contributes to generating information about the current state of antibiotic resistance on the Yucatan coasts for a better understanding of ARGs dissemination and could facilitate the management of ARGs pollution in the environment.

抗生素耐药性（Antibiotic Resistance, AR）是与各类致病菌相关的最重大人类健康与临床挑战之一。近年来，由于人类医疗与畜牧活动中抗生素的广泛使用，其也逐渐演变为一类不容忽视的环境问题。抗生素耐药性的本质源自抗生素耐药基因（Antibiotic Resistance Genes, ARGs），但目前学界对其在海岸环境中的分布情况仍认知有限。因此，本研究旨在通过宏转录组序列（metatranscriptomic sequences）高通量分析，对抗生素耐药基因的组成与丰度进行评估，以此探究尤卡坦（Yucatan）海岸四个采样点的微生物耐药组（microbial resistome）分布特征及其潜在差异。本研究共检出3498种抗生素耐药基因，可介导四环素（tetracycline）、大环内酯类（macrolide）、利福霉素类（rifamycin）、氟喹诺酮类（fluoroquinolone）、氯霉素类（phenicol）、氨基糖苷类（aminoglycoside）、头孢菌素类（cephalosporin）及其他各类抗生素的耐药性。此类抗生素耐药基因的分子耐药机制主要包括外排泵（efflux pump）、抗生素靶点修饰与抗生素靶点替换。同理，所有采样样本中均检出抗生素耐药基因，但各样本的基因富集水平存在显著差异。就采样点而言，所有采集的样本（无论来自保护区域还是污染区域）均检出抗生素耐药基因。值得注意的是，季拉姆（Dzilam）保护区域的沉积物中检出的抗生素耐药基因丰度位列第二，这可能是由海底地下水排泄（submarine groundwater discharge）携带抗生素至海岸所致。总体而言，无论在基因层面还是微生物宿主层面，单类抗生素耐药性的丰度均高于多重耐药性；而微生物的多重耐药性主要通过整合不同的单耐药基因获得。据我们所知，本研究是首个针对尤卡坦海岸不同样本的耐药组进行描述与对比的研究。本研究可为尤卡坦海岸的抗生素耐药性现状提供基础数据，有助于学界更深入地理解抗生素耐药基因的传播扩散，并可为环境中抗生素耐药基因污染的治理工作提供参考依据。