Figure 1.

KEA3 occurs substoichiometrically to the cpATP synthase in the thylakoid membrane. A, Scheme depicting the thylakoid membrane with the main proton transport pathways (i.e. the electron transport chain and the ATP synthase, as well as KEA3). B and C, Representative blots of KEA3 (B) and AtpF (C) quantifications obtained by titrating known amounts of purified recombinant proteins, i.e. the C terminus of KEA3 (which binds the specific epitope antibody, Armbruster et al., 2014) and full-length AtpF, against known amounts of thylakoid membranes (quantified by Chl content). Values derived from the quantifications are given below the blots as average of n = 5 ± sd. D, Ratio of spectral counts identified by MS analysis for the CF_o cpATP b/b` subunits and the CF₁ cpATP synthase subcomplex with KEA3. Average of n = 5 ± sd is displayed.