Fig. 1.
The nucleotide and deduced amino acid sequences of the variable regions of heavy (A) and light chains (B) of scFv (from recombinant phage clone 4). For the light chain, primer-coded amino acid residues at the N-terminus were boxed, and the amino acid sequence determined by direct protein sequencing is given in boldface. The two residues given below the primer-coded sequence represent the primer-introduced difference between the original MAb 20E9 protein sequence and the deduced amino acid sequence of the cloned scFv. Residues corresponding to the complementarity-determining (CDR) regions are shaded and the in-frame TAG stop codon in the VH coding region is underlined. The 20E9 antibody gene fragments were assembled from about 106 hybridoma cells following manufacturer's instructions (Pharmacia, Uppsala).