Fig. 4
The affect of linker loop α5-α6 on NarLC binding to DNA. An EMSA illustrates the relative binding affinities of the indicated NarLC proteins to a 32P-labeled DNA fragment containing an engineered 7-2-7 narG −89/-89 binding site. Lanes 1–5 show increasing concentrations of the specified NarLC protein (from left to right: 0, 0.25, 0.5, 1.0, and 2.0 μM). The binding affinities of NarLC (147–216) and NarLC (131–216), containing helix α6, are equivalent while that of NarLC (126–216), containing helix α6 and loop α5-α6, is relatively reduced