Skip to main content
. 1999 Mar 2;96(5):1898–1903. doi: 10.1073/pnas.96.5.1898

Table 3.

Effects of substituting positively charged side chains in the ligand pocket of the fluorescein-binding BBP variant FluA

Residue Substitution Kd, μM Substitution Kd, μM
FluA wild type 0.427 ± 0.010
His-127 Phe 5.56 ± 0.05
Arg-58 Lys 25.1 ± 2.3
Arg-88 Lys 0.356 ± 0.008 Gln 2.23 ± 0.03
Arg-95 Lys 0.443 ± 0.012 Gln 0.918 ± 0.023
Arg-116 Lys 0.597 ± 0.019 Gln 1.54 ± 0.04

Kd values were measured for 4-glutarylamidofluorescein by fluorescence titration of the protein.