FIG. 2.
Comparison of cross-linked subunit c (cA21C/cM65C) in membrane vesicles of cells expressing the atp operon (FoF1) and cells exclusively expressing the atpE gene (subunit c). Lanes: FoF1, cells of E. coli DK8/pBWU13.NOC were grown in minimal medium with succinate and harvested at an optical density at 578 nm of 0.8 to 1.0; subunit c, cells of E. coli HB1(DE3)/pET22-atpE-c21/65 were grown in ampicillin-containing LB medium to an optical density of 1.0 prior to induction of atpE gene expression with 1 mM IPTG for 1 h. Membranes (20 μg/lane) containing bi-cysteine-substituted subunit c were examined as described in the legend of Fig. 1.