Mechanisms of pollution induced community tolerance in a soil microbial community exposed to Cu

Abstract Pollution induced community tolerance (PICT) to Cu 2+ , and co-tolerance to nanoparticulate Cu, ionic silver (Ag + ), and vancomycin were measured in field soils treated with Cu 2+ 15 years previously. EC 50 values were determined using substrate induced respiration and correlations made against soil physicochemical properties, microbial community structure, physiological status ( q CO 2 ; metabolic quotient), and abundances of genes associated with metal and antibiotic resistance. Previous level of exposure to copper was directly ( P 2+ , and also of nanoparticle Cu. However, Cu-exposed communities had no co-tolerance to Ag + and had increased susceptibly to vancomycin. Increased tolerance to both Cu correlated ( P