Phage-displayed peptides as biosensor reagents

This study investigated the potential to utilize phage-displayed peptides a s reagents in sensor applications. A library of random 12-mers displayed on phage was panned against staphylococcal enterotoxin B (SEB), a causative a gent of food poisoning. Nine SEE binding phage clones were isolated, all of which share the consensus sequence Trp His Lys at their amino terminus. Bi nding of several of these phage was shown to be inhibited when they were as sayed in a competitive enzyme-linked immunosorbent assay (ELISA) format wit h synthesized peptide corresponding to the peptide-encoding region of one o f the clones, Whole phage were labeled with the dye Cy5, and incorporated i nto fluoroimmunoassays, Labeled phage were able to detect SEE down to a con centration of 1.4 ng/well in a fluorescence-based immunoassay, When incorpo rated into an automated fluorescence-based sensing assay, Cy5-labeled phage bound to probes: coated with SEE generated a robust signal of about 10,000 pA, vs a signal of 1000 pA using a control fiber coated with streptavidin, These results demonstrate the potential for development of phage-based sen sor reagents, Copyright (C) 2000 John Wiley & Sons, Ltd.