Fig 5.

Increased relative unsaturated fatty acid levels correlate with increased E. coli killing, lipid peroxidation, and DNA degradation following exposure to a 99.90% copper surface. E. coli strains PDJ1 (recD::Tn10) and MWF1 (fabR::kan recD::Tn10) were grown to mid-log phase (OD₆₀₀, 0.3) in M9 minimal medium supplemented with 0.4% glucose, 0.01% methionine, 0.0005% thiamine, and 25 μg/ml kanamycin or 20 μg/ml tetracycline, respectively. Cells were exposed to 99.90% copper (C11000) coupons, as described for Fig. 2. UFA:SFA is the ratio of unsaturated to saturated fatty acids as reported by Zhang et al. (60). Survival, TBARS production, and DNA degradation were assayed as described for Fig. 2 and 4.