Supplementary Figure 6: In vitro acetylation of His-tagged Integrase.

His-Integrase recombinant protein is purified from E. coli and used as a substrate of P300 acetyl-transferase, in the presence of Ac-CoA. Acetylation occurs, in vitro, upon addition of either full-length P300 protein (second lane) or of its catalytic domain only (third lane), with no difference in yield. As a control, a commercial preparation of Histone Cores (lane 4 and 5) is tested with both enzyme variants. Last two lanes demonstrate how addition of mutated, recombinant version of P300 does not induce acetylation of the Integrase protein or Histones. WB in the bottom panel shows comparable levels of His-tagged Integrase in each preparation. Bands at >75kDa reflect auto-acetylation of P300 enzyme, as previously reported in literature. Anti-His WB is used to confirm the presence of the Integrase recombinant protein in its both acetylated and non-acetylated forms.