TABLE 1.

Binding constants of berenil and CGP 40215A to AT or AATT hairpins

	Steady-state*			Kinetics†
	K (M−1)	ka (M−1 s−1)	kd (s−1)	ka/kd (M−1)
AT hairpin–berenil	3.3 × 107, 4.3 × 105	–	–	–
AATT hairpin–berenil	1.1 × 107	–	–	–
AT hairpin–CGP 40215A	1.7 × 108	7.7 × 106	3.4 × 10−2	2.3 × 108
AATT hairpin–CGP 40215A	7.0 × 107	1.5 × 106	2.1 × 10−2	7.3 × 107

SPR experiments were conducted at 25°C in MES buffer at pH 6.25.

^*Obtained from nonlinear fitting of steady-state responses versus concentrations. The errors from fittings are <5%.

^†Obtained from global kinetics fits of three lowest concentration responses with a mass transport term (Myszka et al., 1998). The errors from fittings are <14%. Berenil kinetics are too fast to be measured under these conditions (see text).