Table 1.

Sedimentation equilibrium analytical ultracentrifugation of Sdk fragments. K_D = dissociation constant. K_I = isodesmic constant. The K_I/K_D ratio is given when it is less than two, indicating the presence of non-specific binding.

DOI: http://dx.doi.org/10.7554/eLife.19058.003

Protein	Oligomeric state	Dimerization KD (μM, n=2)
Sdk1
Ig1–4	Dimer	10.5 ± 1.1
Ig1–5	Dimer	4.6 ± 0.06
Ig1–6	Dimer	2.3 ± 0.39
Ig1–2 dimer interface mutations
Ig1–4 N22R	Monomer	N/A
Ig1–4 K133E	Weak non-specific dimer	204 ± 38.9 (KI/KD  = 1.24)
Ig1–4 L29M/E168D	Dimer	4.26 ± 0.50
Ig1–6 N22R	Monomer	650 ± 66 (KI/KD = 1.05)
Ig3–4 dimer interface mutation
Ig1–4 N253E	Dimer	15.5 ± 1.64
Sdk2
Ig1–4	Dimer	2.2 ± 0.4
Ig1–5	Dimer	0.73 ± 0.036
Ig1–6	Dimer	0.44 ± 0.012
Ig1–2 dimer interface mutations
Ig1–4 H18R/N22S	Monomer	N/A
Ig1–4 N22S	Monomer	N/A
Ig1–4 N22R	Monomer	N/A
Ig1–6 H18R/N22S	Monomer	N/A
Ig3–4 dimer interface mutation
Ig1–4 N253E	Dimer	18.9 ± 0.95
Chimera
Sdk2Ig1–2/Sdk1Ig3–4	Dimer	3.92 ± 0.17