Figure 1.

Staphylococcus haemolyticus is rapidly killed on dry metallic copper (Cu) surfaces and cells accumulate large amounts of Cu. Cells of S. haemolyticus were exposed to dry metallic Cu surfaces (▪) or stainless steel (□) for the indicated times, removed, washed, and plated on solidified growth media. Survivors were counted as colony forming units (CFU) (A). Parallel samples (black bars, from Cu; white bars, from stainless steel) were mineralized and subjected to ICP-MS analysis for determination of cellular Cu content (B, upper panel) or were stained with the Cu(I)-specific fluorescent dye coppersensor-1 and subjected to fluorescence microscopy (B, lower panel). Shown are averages of triplicate experiments with standard deviations (error bars) and representative phase contrast and fluorescence microscopy images, respectively.