Figure 2From: Naturally-occurring, dually-functional fusions between restriction endonucleases and regulatory proteinsAlignment of CR fusion proteins orthologous to C.PvuII and R.PvuII. The PvuII system (top line) is unfused, and shown for comparison. Fully conserved positions or those conserved in 5/6 systems are shaded, and known functional regions (in PvuII) are in bold font (transcriptional activation, recognition helix of the helix-turn-helix motif, dimerization interfaces, Mg++-coordinating residues for REase catalysis (cat), and recognition of the methylated (CH3) base to prevent cleavage. Species sources are as described in the Figure 1 legend. At the lower right, the numbers indicate % amino acid identity (“Ident”) or similarity (“Pos”) for each RM system C or REase (“R”) portion to the corresponding PvuII polypeptide.Back to article page