FAQ: Does isolated genomic DNA purified by different methods change the cleavage rate of Exonuclease V?

Yes. Exonuclease V requires free-ends of ss/ds DNA to act on. Genomic DNA isolated from a spin column more easily digested, as compared to glass-rod spooled DNA. In general, 5 units of Exonuclease V is enough to digest 1 μg of gDNA (HeLa cell) which as been purified by a spin column, and 20 units of Exonuclease V can be used to digest 1 μg of glass-rod spooled E. coli gDNA.