TABLE 3.

Analytical ultracentrifugation analysis to determine K_d All samples were run in 10 mm Tris, pH 7.4, 100 mm NaCl (unless noted otherwise), temperature: 4°C. Speed and protein concentration were as indicated. Model used is M to D, reversible association.

Protein	Speed	[Protein]	Kd
	× 103 rpm	μm	μm
κI O18/O8	15	50	132 ± 1.99
	13	17	189 ± 6.4
		50	257 ± 2.57
	15/13	50	289 ± 2.85
Average with NaCl			217 ± 70.2
Without NaCl	13	50	305.5 ± 3.3
AL-09	15	33	17.8 ± 0.11
		50	7.6 ± 0.07
	13	17	30.6 ± 0.30
		33	18.6 ± 0.20
		50	31.9 ± 0.42
	10	50	25.6 ± 0.28
	13/10	50	29.2 ± 0.32
Average with NaCl			23 ± 8.8
Without NaCl	13	50	34.7 ± 0.28