Table 3. The relationship between the size of an FDAA and its utility in a Gram-negative bacterium.

^aFDAAs were assigned “+++”, ”++”, or “+” if the signal-to-background (S/B) ratio of E. coli BW25113 (WT) images was >4, 2–4, or <2, respectively.

^bData represent the fluorescence intensity ratio of E. coli imp4213 BW25113 to E. coli BW25113 under the same labeling conditions and microscopy settings.