Fig. 2. S. aureus cells accumulate additional copper when cultured in high concentrations of copper. Wild type S. aureus SH1000 were inoculated to a starting OD595nm of 0.05 into TM media (containing glucose) either with (Cu-treated) or without (control) the addition of 1 mM CuSO4, and incubated for 6 h at 37 °C with 180 rpm orbital shaking. Cell densities were determined by OD595nm, and equal cell numbers were harvested, washed to remove surface-bound metals, digested in concentrated HNO3, and elemental composition of the resulting acid lysates was determined by ICP-MS. The symbols represent statistical significance, based on a Student's t-test, where *** = p < 0.0005.
