Figure 2. The Dilated Form of DnaB Interacts Tightly with ^bioχψτ₃δδ’.

(A) Cartoon representation of the SPR experiment used to measure the binding of DnaB versions in solution to immobilized τ₃CLC.

(B) and (C) SPR sensorgrams show association (30 s) and dissociation phases of serially-diluted 0.0625–8 μM DnaB^wt (B) and DnaB^constr (C) on ^bioχψτ₃δδ’, including 0 μM control. Responses at equilibrium, determined by averaging values in the gray region, were fit (insets) using a 1:1 steady state affinity (SSA) model to derive values of K_D (as indicated) and R_max = 440 ± 20 RU (B), 460 ± 20 RU (C). Errors are S.E. of the fit.

(D) DnaB^dilated (250 nM) is injected for 400 s and its dissociation monitored over 2000 s.

(E) Representation of bulk replication assays with rolling-circle substrates in the absence or presence of primase to enable lagging-strand synthesis.

(F) Alkaline agarose gel showing resolved leading- (all lanes) and lagging-strand (DnaG⁺ lanes) products generated by replisomes in the absence of primase (odd lanes) or its presence (even lanes), using DnaB^dilated, DnaB^wt, and DnaB^constr (as indicated).

See also Figure S1.