Fig. 2. Confocal microscope images of (A) fluorogenic click labeling of mitochondria in live U2OS cells treated with 6 and subsequently with d-TCO; targeting of 6 to mitochondria was confirmed by co-localization experiment using Mitotracker green (c and d); (B) fluorogenic labeling using α-d-mannose- and α-d-glucose-specific ConA-dTCO conjugate: (a) negative control (cells treated only with 6, nucleus staining with DRAQ5), (b) live cells labelling with ConA-dTCO followed by addition of 6, (c) live cells incubated with ConA-dTCO, then fixed, permeabilized and treated with 6, (d) cells fixed, permeabilized and treated with ConA-dTCO followed by 6. Click product (ex.: 405 nm, em.: 560–666 nm); DRAQ5 (ex.: 633 nm, em.: 653–732 nm); Mitotracker green (ex.: 496 nm, em.: 505–588 nm). Pictures were processed using LAS AF Lite program.