(A) Multimeric organization of all C-terminal His6-tagged full-length Yyc proteins in this work as observed in blue native polyacrylamide gel electrophoresis (BN-PAGE). Marker proteins in BN-PAGE (kDa): Conalbumin (dimer) 154, BSA (dimer) 132, conalbumin (monomer) 77, BSA (monomer) 66 and ovalbumin 45. The molecular weights (MW) of the Yyc-C-His6 proteins on basis of their amino acid sequence are shown in brackets. As a control, the separation of all purified His6-tagged full-length Yyc proteins by SDS-PAGE is shown in (B). (C)–(E): The apparent discrepancy between the molecular weights and migration distances of the Yyc-C-His6 constructs in BN-PAGE can be solved by application of a conversion factor, which is deduced by linear regression from the correlation of the MW as calculated by amino acid sequence (MW
AA) and the apparent molecular weight observed in BN-PAGE (MW
BPN), respectively. Symbols: YycF (open square), YycG (closed diamond), YycH (closed circle) and YycI (closed triangle).