Figure 6: Disulfide formation at the N terminus.
From: Dual-topology insertion of a dual-topology membrane protein
A 3C mutant in the context of the HA-EmrECless-C+ and Nout-HA-EmrECless-C+ form dimers that are sensitive to the addition of 2-mercaptoethanol suggest that the 3C can form disulfide-linked dimers. No dimers were seen for the Nin-HA-EmrECless-C+ construct. These results are consistent with a 3C location in the oxidizing periplasm for EmrECless-C+ and Nout-HA-EmrECless-C+ constructs and a 3C location in the reducing cytoplasm for the Nin-HA-EmrECless-C+ construct. Further disulfide formation was blocked by the addition of iodoacetamide prior to cell lysis. EmrE is visualized by western blotting for the HA epitope.
