Phages bearing affinity peptides to severe acute respiratory syndromes-associated coronavirus differentiate this virus from other viruses

BACKGROUND: Transmission of SARS-associated coronavirus (SARS-CoV) is now well controlled, nevertheless, it is important to develop effective methods to identify this virus from other pathogens. OBJECTIVES: The purpose of this study was to identify potential ligands and develop a novel diagnostic test to SARS-CoV using phage display technology. STUDY DESIGN: The SARS-CoV spike 1 (S1) protein containing the receptor binding region (RBD) was used as an immobilized target followed by incubation with a 12-mer phage display random peptide library. After four rounds of biopanning, 10 monoclonal phages with specific binding activity to the S1-RBD protein were obtained and subjected to binding and diagnostic assays. RESULTS: DNA sequencing showed that two phage displayed peptides HHKTWHPPVMHL (phage-H) and SQWHPRSASYPM (phage-S) that were specific ligands to the S1 protein. Moreover, the selected phage-H and phage-S were capable of differentiating SARS-CoV from other coronaviruses in indirect enzyme-linked immunosorbent assays. CONCLUSION: The peptides identified in this study are useful reagents for detection of SARS-CoV.