Figure 7. Intermolecular autoacetyl-transferase activity of PopP2 is dependent on the integrity of K383 residue.

A: Detection of acetylated forms of GST-PopP2-^81–488-C321A and GST-PopP2-C321A upon co-expression with GST-PopP2 and GST-PopP2-^81–488, respectively (lane 6 and 7). B: K383R mutation prevents GST-PopP2 to acetylate GST-PopP2^81–488-K383R in trans. The indicated protein combinations were purified from E. coli and their acetylation status tested by immunoblot with an α-Ac-K antibody. The position of acetylated proteins is indicated by dashes (top). GST-purified PopP2 recombinant proteins are shown after Ponceau staining (bottom).