Title: Variations with position of replication errors due to exonuclease warm‐up
Abstract:A.A mismatch errors occuring during poly(dA) replication with the Klenow fragment of E. coli DNA polymerase I have been qualified. The A/T ratio measured for chains extended by 1–25 nucleotides decrea...A.A mismatch errors occuring during poly(dA) replication with the Klenow fragment of E. coli DNA polymerase I have been qualified. The A/T ratio measured for chains extended by 1–25 nucleotides decreases by a factor of at least 15 from beginning to end. The deduced true error rate may decrease by a factor of 2.5 at each successive nucleotide addition. When ddATP is used instead of dATP, the ddA/T ratio indicates little variation of the misincorporation probability with position. Thus, the accuracy improvement in the first case is due to a warm‐up of the proofreading function.Read More