Table 2. K_d values determined by SPR.

Protein	Kd (M)	Fold increase*
WT-C2-domain	(4.2 ± 0.8)×10−7	----
Y96F-C2-domain	(4.3 ± 0.5)×10−7	1
Y96A-C2-domain	(2.4 ± 0.4)×10−6	5.7
N65D-C2-domain	(2.2 ± 0.5)×10−6	5.2

^*Fold increase in K_d relative to the C2-domain binding to POPC vesicles. K_d values were determined from the normalized saturation binding responses (R_eq) at the protein concentrations shown in Figure 4—figure supplement 1 after fitting by nonlinear least squares analysis using R_eq = R_max/(1 + K_d/C).