Fig. 2.

Cross-linking of HTL subunits. (A) Western blots of photo-activatable Tris-bipyridylruthenium(II)–mediated cross-linking (with or without exposure to light radiation) of E. coli IMVs overexpressing either SecYEG or HTL. Y–Y represents a purified covalently-linked SecYEG dimer (38). 106x represents a purified SecE-E dimeric version of SecYEG (4). (B) IMVs were also subjected to DSP-mediated cross-linking, from where the respective complexes were isolated for further analysis by SDS/PAGE and Western blotting. Cross-linking adducts preserved between SecYEG and HTL are bounded in red boxes. Those that are eliminated in the HTL are bounded in green boxes. Newly formed adducts are bounded in blue boxes.