Co-resistance is the dominant mechanism of co-selection and dissemination of antibiotic resistome in nano zinc oxide polluted soil.

The broader soil bacterial community responses at ecotoxicologically relevant levels of nano ZnO (nZnO) focussing on co-selection of antibiotic resistance (AR) were investigated. nZnO imposed a stronger influence than the bulk counterpart (bZnO) on antibiotic resistance genes (ARGs) with multidrug resistance (MDR) systems being predominant (63 % of total ARGs). Proliferation of biomarker ARGs especially for last resort antibiotic like vancomycin was observed and Streptomyces hosted multiple ARGs.

Soil polluted with nano ZnO reveals unstable bacterial communities and decoupling of taxonomic and functional diversities.

Due to relentless production and disposal of nano zinc oxide (nZnO), it has become critical to comprehend the serious risks large-scale accumulation of nZnO pose to bacterial communities in soil. The primary objective was to evaluate the changes in bacterial community structure and associated functional pathways through predictive metagenomic profiling and subsequent validation through Quantitative Realtime PCR in soil spiked with nZnO (0, 50, 200, 500 and 1000 mg Zn kg) and similar levels of bulk ZnO (bZnO). The results revealed that soil microbial biomass-C, -N, -P, soil respiration and enzyme activities decreased markedly at higher ZnO levels.