Figure 6: Nucleotide-binding sites of the 3ADP-bound V₁ complex (3_ADPV₁).

(a,b) Magnified nucleotide-binding site of the ‘half-closed’ (a) and ‘tight-like’ (b) forms in 3_ADPV₁ (as in Fig. 4a), corresponding to the green (Fig. 5c) and red (Fig. 5g) boxes, respectively. The |Fo|-|Fc| maps calculated without ADP:Mg²⁺-SO₄²⁻ (a) and ADP:Mg²⁺ (b) at the binding pockets contoured at 4.0 sigma are shown in red (negative) and green (positive), respectively. SO₄²⁻, cyan; Mg²⁺, green. (c,d) The viewing position, colours and representations of the binding sites correspond to those in the right panel of b. The ‘tight-like’ form (b) in 3_ADPV₁ is superimposed at the adenosine part onto those (shown in transparent grey) of the 2_ADPV₁-‘ADP-bound’ (c) and bV₁-‘tight’ (d) forms.