FIG. 4.

The same pattern of cross-linking is obtained from both A1:B4 and A2:B4 complexes. (a) SecA variant V9C in an A1:B4 complex (top) or an A2:B4 complex (bottom) with every variant of SecB without (left lane of numbered lanes, no dot) or with (right lane of numbered lanes, dot) oxidation. (b) SecA variant G605C subjected to the same treatment. Only the portion of the gels that has the SecA-containing bands is shown. The positions of the protomer of SecA (“A”), cross-linked protomers of SecA and SecB (“A-B”), and the cross-linked dimer of SecA (“A-A”) are indicated.