Figure 1.

Cyclization of l-DNA₆₆ by T4 DNA ligase. Schematic views of the formation of (A) single-stranded DNA ring (c-DNA₆₆) with the assistance of splint-12 nt and (B) polymers from multiple l-DNA₆₆ strands. The single-stranded DNA substrate (l-DNA₆₆) bears a phosphate at the 5′-terminus. (C) Effects of [l-DNA₆₆]₀ on the formation of c-DNA₆₆ and the polymers in 1× T4 ligase buffer (conventional method). The selectivity for the formation of c-DNA₆₆ is presented below the corresponding band. [l-DNA₆₆]₀/[splint-12 nt]₀ = 1/2 at 20°C for 12 h. All the DNA substrate was added to the mixture all at once at the beginning of the reaction.