Fig. 4: The TreX toxin interacts with TrxA.
From: Thioredoxin 1 moonlights as a chaperone for an interbacterial ADP-ribosyltransferase toxin
a Pulldown assays. Soluble extracts of cells producing the indicated proteins (TreX*ST, TreX inactive toxin (E102A mutant) fused to a Strep tag; TrxAH (His-tagged E. coli TrxA) were subjected to Strep, His, or consecutive Strep and His (Strep + His) affinity purifications. Total (T), soluble (S) and elutions (EL) were separated by SDS-PAGE and stained with Coomassie blue (top panel) or transferred onto nitrocellulose membrane and immunodetected with anti-Strep (middle panel) and anti-His (lower panel) antibodies. The 55-kDa band visible by Coomassie staining was identified as GroEL by mass spectrometry. Molecular weight markers (in kDa) are indicated on the left. b Size-exclusion chromatography analysis of purified thioredoxin TrxA (black line), immunity protein TriX (green line), and TreX*-TriX (blue line), TreX*-TrxA (red line) and TreX*-TriX-TxrA (purple line) complexes. Elution volumes of known molecular weight protein standards are indicated. Peak fractions were subjected to SDS-PAGE and Coomassie blue staining (bottom panel) confirmed the presence of the expected proteins.
