FIG. 5.

Partial purification and separation of acetylated and nonacetylated OGG1 from HeLa nuclear extract. (A) Outline of purification steps of OGG1 from HeLa nuclear extract. (B) Eluted fractions from the phosphocellulose column were assayed for 8-oxoG excision activity as described in Materials and Methods. S, substrate; P, product. (C) Western analysis for AcOGG1 in phosphocellulose fraction (upper panel). The same blot was reprobed with OGG1 antibody (lower panel). (D) Specific activity and analysis of trapped complexes of endogenous AcOGG1 (PC200) and unmodified OGG1 (PC250). OGG1 (10 nM) was incubated at 37°C in 15 μl with 100 nM 8-oxoG·C oligonucleotide in the presence or absence of 100 nM of E. coli Nfo for 10 min, as described in Materials and Methods. S, substrate; P, product.