Table 2.

Sedimentation equilibrium measurements of protomer-protomer affinities for AsiA and mutant AsiA proteins^a

	Ka (M−1)	Kd (µM)	ΔG° (kJ/mol)b	mass (kDa)c
WT	2.8 ± 0.8 × 106	0.35 ± 0.10	−36.8 ± 0.7	10.90 ± 0.08
M1A	3.8 ± 1.0 × 106	0.26 ± 0.07	−37.6 ± 0.6	12.33 ± 0.08
V14A	8.2 ± 1.2 × 105	1.2 ± 0.2	−33.7 ± 0.4	10.23 ± 0.07
I17A	2.0 ± 0.2 × 105	4.9 ± 0.6	−30.3 ± 0.3	13.49 ± 0.13
K20A	2.1 ± 0.4 × 106	0.48 ± 0.10	−36.1 ± 0.5	12.62 ± 0.09
F21A	4.7 ± 1.9 × 106	0.21 ± 0.09	−38.0 ± 1.0	11.87 ± 0.11
E39A	5.7 ± 2.0 × 106	0.18 ± 0.06	−38.5 ± 1.0	12.58 ± 0.09
I40A	3.6 ± 0.5 × 105	2.7 ± 0.4	−31.7 ± 0.3	10.72 ± 0.09
I17A/I40Ad	1.4 ± 0.3 × 103	694 ± 0.149	−18.0 ± 0.5	11.47 ± 0.27

^aFits are to a monomer-dimer self-association model and are from data acquired at three speeds for three protein concentrations monitored at 230 nm unless otherwise noted. Error limits are standard deviations from Monte Carlo simulations.

^bFree energy of association.

^cFitted monomer molecular mass. The actual AsiA molecular mass is 10.59 kDa.

^dBased on data collected at a single speed at higher concentrations monitored at 280 nm (see text).