Figure 6. Influence of substrate binding on OAD and OAD subunits.

A. OAD REES variations in the absence of substrates (a) or in the presence of either 250 mM NaCl (b) or 10 mM oxomalonate (c). OAD was purified in 250 mM KCl, pH 7.4, 0.5% Tween 20, 0.05% Brij 58, 100 mM KH₂PO₄ buffer. REES of OAD in KCl-containing buffer (i.e. 3.8 nm, not shown) was taken as reference to calculate the REES variation. B. Na⁺ (250 mM) influence on REES variation of carboxyltransferase domain of the α subunit (a), reconstituted carboxyltransferase and biotin binding domain of the α subunit (b), the whole α subunit (c), αγ complex (d), and the OAD complex (e).