FIGURE 4.

In vitro interactions of EhNO with ferredoxin. A, SDS-PAGE analysis of the complex of EhNO and ferredoxin is shown. Protein mixtures were incubated for 30 min with (even lane numbers) and without (odd lane numbers) 5 mm carbodiimide, electrophoresed on a 15% SDS-PAGE gel under reducing conditions, and then stained with Coomassie Brilliant Blue R250. The examined protein mixtures were as follows: lanes 1 and 2, spinach (S. oleracea) ferredoxin:NADP⁺ reductase (SoFNR) + spinach ferredoxin (SoFd); lanes 3 and 4, EhNO1+SoFd; lanes 5 and 6, EhNO2+SoFd; lanes 7 and 8, EhNO1+EhFd1; lanes 9 and 10, EhNO2+EhFd1. Protein bands corresponding to the cross-linked proteins are indicated by an asterisk. The positions of the purified proteins are indicated on the right side of the gel. B, shown is an immunoblot analysis of the cross-linked samples using an anti-His antibody.