Figure 1.
A one-step method for constructing libraries. With e-PERMUTE, libraries are created by mixing a circular gene, a permuteposon and MuA. The transposase inserts the permuteposon into the circular gene in two orientations. In the orientation that is designated as parallel, the regulatory elements, i.e. promoter (Pc) and RBS, and the permuted genes are in the same orientation. When an ORF is parallel and in frame, a circularly permuted protein is expressed with an 18-residue peptide amended to the new N-terminus. In the antiparallel orientation, the regulatory elements and the permuted AK genes are in different orientations such that the antisense strand of each permuted gene is transcribed. In this case, the permuted protein cannot be translated.