Figure 4. Preparation, identification and characterization of PdhR.
(A) SDS-PAGE (12%) analysis of purified PdhR.
The molecular weights of the standard protein markers (Biorad) are labeled at the left. The N-terminal tagged PdhR protein with an expected size (~32 kDa) is indicated by an arrow.
(B) Chemical cross-linking assays for the solution structure of the PdhR protein.
Ethylene glycol bis-succinimidylsuccinate (EGS) was the cross-linker. The triangle on the top represents the addition of EGS cross linker in varied concentrations (0, 5, 10, 20, 50 μM in the right-hand five lanes [left to right]). M: Molecular weight. The monomeric PdhR protein size is predicted to be ~32 kDa, and thus the dimeric weight is ~64 kDa.
(C) MS identification of the purified PdhR protein
The tryptic peptides with hits to the PdhR sequence are given in bold underlined type.