Serrana Joeselle M, Nascimento Francisco J A, Dessirier Benoît, Broman Elias, Posselt Malte
Stockholm University Center for Circular and Sustainable Systems (SUCCeSS), Stockholm University, 106 91, Stockholm, Sweden.
Department of Environmental Science (ACES), Stockholm University, 106 91, Stockholm, Sweden.
Microbiome. 2025 Apr 7;13(1):92. doi: 10.1186/s40168-025-02086-x.
Antimicrobial resistance is a major global health concern, with the environment playing a key role in its emergence and spread. Understanding the relationships between environmental factors, microbial communities, and resistance mechanisms is vital for elucidating environmental resistome dynamics. In this study, we characterized the environmental resistome of the Baltic Sea and evaluated how environmental gradients and spatial variability, alongside its microbial communities and associated functional genes, influence resistome diversity and composition across geographic regions.
We analyzed the metagenomes of benthic sediments from 59 monitoring stations across a 1,150 km distance of the Baltic Sea, revealing an environmental resistome comprised of predicted antimicrobial resistance genes (ARGs) associated with resistance against 26 antibiotic classes. We observed spatial variation in its resistance profile, with higher resistome diversity in the northern regions and a decline in the dead zones and the southern areas. The combined effects of salinity and temperature gradients, alongside nutrient availability, created a complex environmental landscape that shaped the diversity and distribution of the predicted ARGs. Salinity predominantly influenced microbial communities and predicted ARG composition, leading to clear distinctions between high-saline regions and those with lower to mid-level salinity. Furthermore, our analysis suggests that microbial community composition and mobile genetic elements might be crucial in shaping ARG diversity and composition.
We presented that salinity and temperature were identified as the primary environmental factors influencing resistome diversity and distribution across geographic regions, with nutrient availability further shaping these patterns in the Baltic Sea. Our study also highlighted the interplay between microbial communities, resistance, and associated functional genes in the benthic ecosystem, underscoring the potential role of microbial and mobile genetic element composition in ARG distribution. Understanding how environmental factors and microbial communities modulate environmental resistomes will help predict the impact of future environmental changes on resistance mechanisms in complex aquatic ecosystems. Video Abstract.
抗菌药物耐药性是全球主要的健康问题，环境在其出现和传播中起着关键作用。了解环境因素、微生物群落和耐药机制之间的关系对于阐明环境耐药组动态至关重要。在本研究中，我们对波罗的海的环境耐药组进行了特征分析，并评估了环境梯度和空间变异性以及其微生物群落和相关功能基因如何影响不同地理区域的耐药组多样性和组成。
我们分析了波罗的海1150公里距离内59个监测站的底栖沉积物宏基因组，揭示了一个由与26类抗生素耐药性相关的预测抗菌药物耐药基因（ARG）组成的环境耐药组。我们观察到其耐药谱存在空间变化，北部地区的耐药组多样性较高，而死区和南部地区则有所下降。盐度和温度梯度以及养分可用性的综合作用创造了一个复杂的环境格局，塑造了预测ARG的多样性和分布。盐度主要影响微生物群落和预测的ARG组成，导致高盐度区域与中低盐度区域之间存在明显差异。此外，我们的分析表明，微生物群落组成和移动遗传元件可能对塑造ARG多样性和组成至关重要。
我们提出盐度和温度被确定为影响不同地理区域耐药组多样性和分布的主要环境因素，养分可用性进一步塑造了波罗的海的这些模式。我们的研究还强调了底栖生态系统中微生物群落、耐药性和相关功能基因之间的相互作用，强调了微生物和移动遗传元件组成在ARG分布中的潜在作用。了解环境因素和微生物群落如何调节环境耐药组将有助于预测未来环境变化对复杂水生生态系统中耐药机制的影响。视频摘要。
