Fig. 2From: Rapid characterization of CRISPR-Cas9 protospacer adjacent motif sequence elementsPAM preferences for S. pyogenes (a), S. thermophilus CRISPR3 (b), and S. thermophilus CRISPR1 (c) Cas9 proteins. Frequency of nucleotides at each PAM position was independently calculated using a position frequency matrix (PFM) [21] and plotted as a WebLogo [23]Back to article page