Table 3.
Kd, μM |
Error | ΔG, kcal mol−1 |
ΔΔGaffinity, kcal mol−1 |
ΔΔGspecificity,b kcal mol−1 |
||
---|---|---|---|---|---|---|
|
||||||
Src | Arg | 37 | 2 | −6.0 | 0 | +0.7 |
Dap-Ac | 350 | 31 | −4.7 | 1.33 | −0.2 | |
hArg(gGly) | 59 | 2.3 | −5.8 | 0.28 | −0.6 | |
hArg(gl-Val) | 67 | 2.3 | −5.7 | 0.35 | −0.7 | |
hArg(gd-Val) | 130 | 3.7 | −5.3 | 0.74 | −0.4 | |
hArg(gl-Phe) | 58 | 1.8 | −5.8 | 0.27 | −0.5 | |
hArg(gd-Phe) | 66 | 2.1 | −5.7 | 0.34 | −0.9 | |
hArg(gl-Trp) | 24 | 1.2 | −6.3 | −0.26 | −1.0 | |
hArg(gd-Trp) | 49 | 2.1 | −5.9 | 0.17 | −1.0 | |
Grb | Arg | 12 | 0.7 | −6.7 | 0 | |
Dap-Ac | 500 | 160 | −4.5 | 2.20 | ||
hArg(gGly) | 166 | 12 | −5.1 | 1.56 | ||
hArg(gl-Val) | 227 | 13 | −4.9 | 1.74 | ||
hArg(gd-Val) | 270 | 31 | −4.9 | 1.84 | ||
hArg(gl-Phe) | 128 | 8 | −5.3 | 1.40 | ||
hArg(gd-Phe) | 319 | 44 | −4.8 | 1.94 | ||
hArg(gl-Trp) | 121 | 10 | −5.3 | 1.36 | ||
hArg(gd-Trp) | 244 | 24 | −4.9 | 1.78 |
ΔΔGaffinity = ΔG (peptide) – ΔG (Arg).
ΔΔGspecificity = ΔGSrc – ΔGGrb for a given peptide. All peptides except hAMII(Arg) (Kd = 102 ± 7 μM, ΔGCrk = −5.4 kcal mol−1), hAMII(gl-Trp) (Kd = 153 ± 9 μM, ΔGCrk = −5.2 kcal mol−1), and hAMII(gd-Trp) (Kd = 183 ± 11 μM, ΔGCrk = −5.1 kcal mol−1) bound poorly to Crk (Kd > 250 μM). All experiments were conducted in PBS at 25 °C.