(a) Optical density profile of 5 μM FKBP-V48 in presence of stoichiometric amount of CID (filled triangles) and control (filled circles). (b) Decrease in transition temperature of 5 μM FKBP-V48 by stoichiometric CID binding (n = 3), Paired t-test, p = 0.007, R2 = 0.98 (c) Optical density profile of 4 μM FKBP-V72 in presence of stoichiometric amount of CID (filled triangles) and control (filled circles). (d) Decrease in transition temperature of 4 μM FKBP-V72 by stoichiometric CID binding (n = 3), Paired t-test, p = 0.023, R2 = 0.95.