Diversity Comparison of T7 and M13 Phage-Displayed Peptide Libraries

Abstract

Phage-displayed peptide libraries have become widely used screening resources for identification of protein ligands. improvements in library diversity should result in higher success rates of affinity screenings. Previous research identified amino acid biases within M13-displayed peptide libraries which resulted in decreased peptide library diversity. Further research suggested that due to the differing processes of phage morphogenesis, the use of T7 phage in peptide library construction could relieve the M13-associated amino acid biases and thus produce more diverse peptide libraries. In this study a T7-displayed peptide library was constructed with a carboxyl-terminal streptavidin affinity sequence for confirmation of peptide surface display. Diversity analyses of a peptide population from the library were compared to diversity analyses of the M13 Ph.D.-12 library and a T7 random 12-mer peptide library. The results confirmed the previous hypothesis of increased peptide diversity with the use of T7 phage in peptide library construction.