Figure 8.

(a) Cross-catalyzed replication of template molecules E and E’ from their building blocks A⁽’⁾ and B⁽’⁾. (b) Secondary structure of the template duplex. The curved arrow denotes the site of ligation of the building blocks, the dashed boxes include the sequences to be mutated and the solid lines indicate the sites of the G∙U base pairs inducing the wobble that enhances catalytic activity. (c) The altered sequences of the 12 different template molecules, the E’ molecules have complementary sequences in the base pairing part (horizontal) and identical sequences in the catalytic part (vertical). Dark circles denote the differences relative to E1 [45].