Summary: Off-target binding and cleavage by Cas9 pose major challenges in its application. How the conformational dynamics of Cas9 govern its nuclease activity under on- and off-target conditions remains largely unknown. Here. using intra-molecular single-molecule fluorescence resonance energy transfer measurements. https://www.nacrack.com/quick-save-PPSS-Group-Covert-Stab-Body-Armour-limited-save/