Dissociation kinetics of mutant scFv at 25°C. (A)
Yeast displaying mutant scFv isolated from a random library was assayed
for antigen dissociation rate. The 4-4-20 and VHS95A values
were calculated from fluorescence quenching data with soluble scFvs.
Dissociation rates for barnase/barstar (45), streptavidin/biotin
(46), avidin/biotin (46), and trypsin/bovine pancreatic trypsin
inhibitor (BPTI) (47) are indicated for comparison. (B)
Dissociation kinetics of purified, soluble 4 M5.3 and 4-4-20 scFvs were
assayed by fluorescence quenching. Triplicate traces for 4-4-20 scFv in
PBS (150 mM NaCl/10 mM sodium phosphate buffer, pH 8) are shown, and
12 independent replicates are shown for 4 M5.3 in PBS or LSB.
τ1/2, half-time for dissociation.