Details

Autor(en) / Beteiligte

• Xu, Risheng
• Zhang, Yuhan
• Li, Yue
• Song, Jianxiao
• Liang, Yanru
• Chen, Fan
• Wei, Xiaomeng
• Li, Cui
• Liu, Wenbo
• Rensing, Christopher
• Wang, Yuheng
• Chen, Yanlong

Titel

Linking bacterial life strategies with the distribution pattern of antibiotic resistance genes in soil aggregates after straw addition

Ist Teil von

• Journal of hazardous materials, 2024-06, Vol.471, p.134355-134355, Article 134355

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2024

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Straw addition markedly affects the soil aggregates and microbial community structure. However, its influence on the profile of antibiotic resistance genes (ARGs), which are likely associated with changes in bacterial life strategies, remains unclear. To clarify this issue, a soil microcosm experiment was incubated under aerobic (WS) or anaerobic (AnWS) conditions after straw addition, and metagenomic sequencing was used to characterise ARGs and bacterial communities in soil aggregates. The results showed that straw addition shifted the bacterial life strategies from K- to r-strategists in all aggregates, and the aerobic and anaerobic conditions stimulated the growth of aerobic and anaerobic r-strategist bacteria, respectively. The WS decreased the relative abundances of dominant ARGs such as QnrS5, whereas the AnWS increased their abundance. After straw addition, the macroaggregates consistently exhibited a higher number of significantly altered bacteria and ARGs than the silt+clay fractions. Network analysis revealed that the WS increased the number of aerobic r-strategist bacterial nodes and fostered more interactions between r-and K-strategist bacteria, thus promoting ARGs prevalence, whereas AnWS exhibited an opposite trend. These findings provide a new perspective for understanding the fate of ARGs and their controlling factors in soil ecosystems after straw addition. Straw soil amendment has been recommended to mitigate soil fertility degradation, improve soil structure, and ultimately increase crop yields. However, our findings highlight the importance of the elevated prevalence of ARGs associated with r-strategist bacteria in macroaggregates following the addition of organic matter, particularly fresh substrates. In addition, when assessing the environmental risk posed by ARGs in soil that receives crop straw, it is essential to account for the soil moisture content. This is because the species of r-strategist bacteria that thrive under aerobic and anaerobic conditions play a dominant role in the dissemination and accumulation of ARG. [Display omitted] •The bacterial life strategies and ARGs in aggregates were investigated after straw addition.•r- more than K-strategist bacteria community were closely related to ARGs profiles.•The aerobic/anaerobic r-strategist bacteria were dominant factors controlling the fate of ARGs.•Macroaggregates were hotspots for connections between ARGs and bacteria after straw addition.