CHARACTERIZATION OF FV FRAGMENTS EXPRESSED ON PHAGE SURFACE

We characterized a phage antibody in which an Fv fragment, namely, a f ree V-H fragment noncovalently associated with a V-L fragment that is fused with a truncated cpIII molecule (V-L-Delta cpIII), is expressed can the phage surface. D1.3 antibody specific for hell egg-white lysoz yme was used as a model system. Both V-H and V-L-Delta cpIII fragments were stably expressed and associated with each other to form a faithf ul antigen-binding site. The results of Western blotting indicated tha t more than 5% of phages expressed the Fv fragment on their surface. A nalysis of the kinetics of binding of the phage antibody to the antige n suggested the possibility of presence of phages having multiple-bind ing sites can a single phage particle.