Figure 3.
Dependence of the normalized friction coefficient ξ (rl)/ξ (0) of a single-labeled (Models 1–4) or double-labeled (Model 5) EcoRV on the radius rl of the label(s): (1) linear diffusion with a rigid linker, (2) rotational diffusion with a rigid linker, (3) linear diffusion with a flexible linker, (4) rotational diffusion with a flexible linker, (5) rotational diffusion with a rigid linker. EcoRV is presented schematically in magenta, DNA in green and the label in orange. Experimental normalized friction coefficients ξ (in red) are calculated using ξ (rl)/ξ (0) = DCy3B/D1, where DCy3B is the linear diffusion constant of EcoRV labeled with Cy3B, and D1 is the linear diffusion constant of a protein variant with one or two label(s) of radius rl.