Fig. 3
From: Divergent methylation of CRISPR repeats and cas genes in a subtype I-D CRISPR-Cas-system
DNA 5mCGATCG methylation of the plasmid pSYSA in Synechocystis 6803 measured by bisulfite analysis. Percentages of 5mCGATCG methylation are plotted for the forward strand (upper panel) and reverse strand (lower panel) of the pSYSA plasmid. Duplicate analyses were performed, using DNA from the wild-type (WT) strain (blue circles) and a ∆sll0729 mutant (orange circles) that does not impact 5mCGATCG methylation. The location of cas genes and the repeat-spacer array (R-S) is given on top. The asterisks label two undermethylated motifs within the gene slr7010. In the Synechocystis 6803 reference strain pSYSA is 103,307 nt long [51] and the CRISPR1 repeat-spacer array extends from positions 16,310 to 19,901 and consists of 50 repeats. The segment from position 19,901 to 26,797 contains no CGATCG sites. Methylation is lower for repeat instances 22 and 44 on the reverse strand