Temperature shapes a modular division of labor among soil fungi to facilitate antibiotic dissipation.

The antibiotics used in veterinary medicine accumulate in agricultural soils, where their persistence selects for antibiotic-resistance genes (ARGs). Soil fungi possess diverse metabolic enzyme systems and substantial potential for antibiotic biodegradation, but how temperature shapes fungal community succession and the functional pathways involved in antibiotic removal remains poorly understood. Herein, soils with histories of no fertilizer and organic fertilizer application (UF and OF, respectively) were spiked with 21 tetracyclines, quinolones and sulfonamides at approximately 2 mg kg-1 per compound and incubated for 18 months at natural (NT; monthly mean of approximately 15 °C, ranging from -5.6 °C to 28.1 °C), constant (CT, 20 °C), and low (LT, 4 °C) temperatures. Dissipation kinetics were combined with fungal community and metagenomic profiling, co-occurrence networks, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway-residual correlations. Dissipation was slower in OF (total-antibiotic half-life [DT50] of 22-58 d) than in UF (DT50 of 18-44 d). Temperature exerted a stronger effect, with dissipation fastest at NT (DT50 of 18-22 d) and slowest at LT (DT50 of 44-58 d); ARGs followed the same trend, declining less than the parent compounds and least of all at LT. Temperature restructured the fungal community (PERMANOVA, P ≤ 0.018), chiefly by replacing taxa rather than by nested loss. Fungal-assigned KEGG pathways were inversely correlated with residual antibiotic concentrations (Spearman's ρ = -0.34 to -0.54, P < 0.05) and fell into three candidate functional modules: antibiotic capture and transport, oxidative transformation, and intracellular transformation. Across all temperatures the community retained a capture-and-transport core, for which no significant temperature contrast was detected, whereas oxidative and intracellular transformation were both less abundant at LT. Temperature therefore influences soil antibiotic dissipation by reshaping fungal community structure and redistributing annotated potential among complementary fungal functions. Accounting for this temperature dependence can improve bioremediation strategies for antibiotic-contaminated agricultural soils.