Figure 1

Principle of uracil-excision based DNA fusion. In uracil-excision based DNA fusions, dU nucleotides replace selected thymidine nucleotides in DNA and is subsequently removed by e.g. the USER™ enzyme, leaving the upstream nucleotide sequence unstable. When the resulting, compatible single stranded overhangs are combined they can be transformed directly into bacteria without prior ligation to yield a stable recombinant molecule.