Sadikalay Syndia, Cavé Laura, Ducat Célia, Mauriello Gwénola, Berchel Mylène, Boismoreau Didier, Guyomard Stéphanie, Nazaret Sylvie, Talarmin Antoine, Ferdinand Séverine
Unit of Health and Environment, Institut Pasteur de Guadeloupe, Les Abymes, France.
Research Group on « Multi-résistance environnementale et efflux bactérien », UMR Ecologie Microbienne CNRS/INRA-1418/Université de Lyon, Villeurbanne, France.
PLoS One. 2025 Aug 13;20(8):e0329200. doi: 10.1371/journal.pone.0329200. eCollection 2025.
The dissemination of antibiotic resistant bacteria (ARB) and genes is one factor responsible for the increasing antibiotic resistance and the environment plays a role in resistance spread. Animal excreta can contribute to the contamination of the environment with ARBs and antibiotics and in some cases, environmental bacteria under antibiotic pressure may acquire antibiotic resistance genes (ARGs) from ARBs by horizontal gene transfer. In Guadeloupe, a French overseas department, organic amendments derived from human and animal waste are widely used in soil fertilization, but their contribution to antibiotic resistance remains unknown. The objective of this study was to evaluate the impact of composting animal and human raw waste and the repeated application of their derived-composts, on the fate of ARGs and antibiotic resistant Enterobacteria, for the first time, in tropical soils of Guadeloupe used for vegetable production. An unculturable approach was used to characterize the bacterial community composition and ARG content from raw waste to composts. A cultivable approach was used to enumerate Enterobacteria, and resistant isolates were further characterized phenotypically and genotypically. Based on this original approach, we demonstrated that the raw poultry droppings exhibited a depletion of Escherichia and Shigella populations during the composting treatment, which was corroborated by the results on the culturable resistant Enterobacteria. Significant differences in the abundance of ARGs were also observed, with some gene levels increasing or decreasing after composting. In addition, other bacterial genera potentially involved in the spread of antimicrobial resistance were identified. Taken together, these results demonstrate that successive applications of raw waste-derived-composts from green waste, sewage sludge, and poultry droppings reshape the Enterobacterial community and influences the abundance of ARGs, with some gene levels increasing or decreasing, in Guadeloupe's tropical vegetable production soils.
抗生素抗性细菌（ARB）和基因的传播是导致抗生素耐药性增加的一个因素，环境在耐药性传播中起一定作用。动物排泄物会导致环境被ARB和抗生素污染，在某些情况下，处于抗生素压力下的环境细菌可能通过水平基因转移从ARB获得抗生素抗性基因（ARG）。在法属海外省瓜德罗普岛，源自人类和动物粪便的有机改良剂被广泛用于土壤施肥，但其对抗生素耐药性的影响尚不清楚。本研究的目的是首次评估在瓜德罗普岛用于蔬菜生产的热带土壤中，动物和人类原生废物堆肥以及重复施用其衍生堆肥对ARG和抗生素抗性肠杆菌命运的影响。采用不可培养方法来表征从原生废物到堆肥的细菌群落组成和ARG含量。采用可培养方法来计数肠杆菌，并对耐药分离株进行进一步的表型和基因型特征分析。基于这种原始方法，我们证明了在堆肥处理过程中，生禽粪便中的大肠杆菌和志贺氏菌种群减少，这与可培养的耐药肠杆菌的结果一致。还观察到ARG丰度存在显著差异，一些基因水平在堆肥后增加或减少。此外，还鉴定出了其他可能参与抗菌素耐药性传播的细菌属。综上所述，这些结果表明，在瓜德罗普岛的热带蔬菜生产土壤中，连续施用来自绿色废物、污水污泥和禽粪便的原生废物衍生堆肥会重塑肠杆菌群落，并影响ARG的丰度，一些基因水平会增加或减少。
