An M13 phage library displaying random 38-amino-acid peptides as a source of novel sequences with affinity to selected targets.
We have examined the potential of isolating novel ligands from a library of M13 pIII-fusion phage displaying peptides composed of 38 random amino acids (aa). The library was panned with streptavidin (SA) and a polyclonal goat antimouse IgG Fc antibody (Ab) preparation coupled to paramagnetic beads. SA selected two classes of phage from the library. One class exhibited the aa motif, HP(Q/M) theta (where theta signifies a non-polar aa), similar to the motif identified by Devlin et al. [Science 249 (1990) 404-406] using a 15-aa random peptide library displayed on phage. The other class of phage had no discernible motif. In binding experiments, the non-HP(Q/M) theta phage had a slightly higher affinity for SA than did the motif phage. Both classes of SA-binding phage failed to bind native and non-glycosylated forms of avidin, even though SA and avidin are structurally similar and both proteins possess extraordinary affinities for biotin. The polyclonal goat anti-mouse IgG Fc Ab preparation selected phage displaying sequences similar to a region of the mouse IgG Fc. Thus, a single immunodominant epitope on the mouse IgG Fc was identified. Furthermore, a second phage displaying peptides with no discernible sequence similarities to mouse IgG Fc was isolated. Thus, an M13 library displaying 38-aa peptides can yield phage with affinity for various targets. Finally, we have observed a biological bias against odd numbers of Cys residues in the displayed peptides.
Department of Biology, University of North Carolina, Chapel Hill 27599-3280.
B K
BK
Kay
N B
NB
Adey
Y S
YS
He
J P
JP
Manfredi
A H
AH
Mataragnon
D M
DM
Fowlkes
D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism; D017104:Bacteriophage M13 / Q000235:genetics*; D001483:Base Sequence; D001665:Binding Sites; D003001:Cloning, Molecular / Q000379:methods; D003545:Cysteine / Q000378:metabolism; D004220:Disulfides / Q000378:metabolism; D006041:Goats / Q000276:immunology; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010455:Peptides / Q000032:analysis* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000378:metabolism*; D019809:Streptavidin
D001426:Bacterial Proteins; D004220:Disulfides; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D009838:Oligodeoxyribonucleotides; D010455:Peptides; D011993:Recombinant Fusion Proteins; D019809:Streptavidin; D003545:Cysteine