Screening for PreS specific binding ligands with a phage displayed peptides library

Figure 4 Synthesis of thio-PreS. A: a schematic representation of the thio-PreS fusion protein, DDDDK is a cleavage site of rEK; B: SDS-PAGE analysis. Lane 1, the E.coli lysate without IPTG induction; lane 2, the soluble lysate after IPTG induction, thio-PreS of 33 ku is indicated with a triangle; lane 3, the purified thio-PreS; C: Western blot with the anti-thio mAb. Lane 1, thio-PreS coupled to the Thiobond^TM beads; lane 2, thio-PreS coupled beads treated in the absence of rEK; lane 3, thio-PreS coupled beads treated in the presence of rEK.