Fig. 4. Super-resolution SIM imaging revealing localization of 4⁴⁺ in S. aureus SH1000 cells at (A) 5 min and (B) 60 min. Cells images using the emission of 4⁴⁺ on excitation at 450 nm using the A568 filter. After treatment with 4 μM 4⁴⁺, cells were washed with PBS before fixing with paraformaldehyde (4%).