Results and discussion
In this study, to overcome the barrier of limited transformation efficiency of E. coli in the preparation of high quality phage display libraries, we adopted a novel protein engineering technology in which amino PSI-7976 residues at 12 different places were randomly substituted using a gene shuffling method to enhance the usefulness of the phage display technique.
Table 1.
Substituted residues and affinities of TNF receptor-selective mutant candidates.
Amino acid sequence
Relative affinity (%)a
293132848586878889145146147TNFR1TNFR2TNFR1/TNFR2
wtTNFLRRAVSYQTAES100.0100.01.0
R1-5bKAG–––––––ST82.02.0 × 10?24.1 × 103
R1-15RNYS–R–NP–––115.76.0 × 10?21.9 × 103
R1-16TQYTPG–SH–AH8.66.0 × 10?21.4 × 102
R1-17RTFSPL–RQSST54.26.0 × 10?29.0 × 102
R1-18KNFSSH–TH–––53.91.0 × 10?15.4 × 102
R1-19SNY–––––––V–138.78.0 × 10?11.7 × 103
R1-20T–YSHT—PSSQA170.53.0 × species 10?25.7 × 103
R2-3c–––––––––R–T