PAM-interacting domain turn-helix 51 motifs can improve Cas9–SpRY activity

This report demonstrates the importance of interactions between motifs of the Cas9-SpRY nuclease and DNA sequence downstream of the PAM (post-PAM). These motifs can be critical to the activity of Cas9 for its nuclease and prime editing functions. The Cas9-SpRY enzyme used in the paper targets a wide range of PAM sequences enabling a broad range of potential therapeutic targets. The PAM specificity of engineered Cas9-SpRY and its variants in this paper was determined using myTXTL Pro for the PAM analysis assay. With myTXTL, only DNA templates as inputs are required with no need for separate transcription or protein expression/purification steps.