Fig 3.

TatAcCd and TatAcCy form discrete complexes. To investigate complex formation, TatCd-StrepII, TatCy-StrepII, TatAc-StrepII, TatAc-TatCd-StrepII, or TatAc-TatCy-StrepII were expressed in E. coli ΔtatABCDE. Next, membranes from the respective cells were isolated. Membrane proteins were then solubilized in 2% digitonin and separated by blue native PAGE. The gels were immunoblotted using StrepII-specific antibodies and a secondary anti-mouse IgG-horseradish peroxidase conjugate. The EZ-ECL detection kit was used to visualize bound antibodies. The mobility of molecular mass markers (left panel) and StrepII-tagged proteins and complexes is indicated (kDa). TatCd* indicates a TatCd complex with higher molecular weight.