Table 1.

Summary of the electrophoretic mobility shift assays with various Lac constructs

Protein	Operator binding affinity,* M			Bend angle,† °
	Wild type	SymL(−1)	SymR(+1)	Wild type	SymL(−1)	SymR(+1)
LacI‡	3  × 10−11	2.4  × 10−11	9  × 10−11	68	72	56
Wild-type HP62‡	1  × 10−6	0.8  × 10−6	n.d.b.‖	28	35	n.d.b.
HP62-V52C (red)§	2  × 10−7			23	33	17
HP62-V52C (ox)¶	3  × 10−11	1.8  × 10−11	15  × 10−11	25	36	17

^*The binding affinities for the SymL(−1), wild-type, and SymR(+1) operators were determined at 4°C from four independent experiments and scaled to the value found for the wild-type probe. Values represent apparent K_ds and refer to the protein concentration where 50% of the DNA operator is bound to the protein. 

^† Bend angle was determined by circular permutation method and is the average of three independent experiments. The standard deviation in the bending angles determined in repeated experiments is 10%. 

^‡ Relative affinities and bend angles for LacI and Wt-HP62 were taken from Spronk et al. (6). 

^§ Reduced state. 

^¶ Oxidized state. 

^‖ No detectable binding.