Figure 1.

Construction of peptide aptamer library. (A) Ribbon diagrams of Staphylococcus aureus nuclease (SN) protein. The scaffold protein SN consisted of five β-strands and three helices. The sequences S₆₃L₆₄R₆₅K₆₆A₆₇ which displaying the exserted loop was shown as scarlet stick representation. (B) The scheme for cloning random sequences to pTRG-SN vector. The double-stranded DNA were produced by employing single-stranded oligonucleotides containing randomized (NNS)₁₆ nucleotide triplets as templates, followed by the digestions with Eco RI/Bgl II, and ligated into plasmid pTRG-SN which pre-cut with same enzymes.