Figure 2: Proofreading DNA polymerases can be inhibited by certain primers.
From: Guanine-rich sequences inhibit proofreading DNA polymerases
(A) Example of inhibitory primer using PSGXL. A slightly longer target DNA fragment can be successfully amplified by the primers OuterR and Stat3F, but use Stat3R instead of OuterR caused PCR failure. (B) Primers Stat3R and GfapR are inhibitory to PSGXL and PS, but not to LATaq and Taq. The 2 kb targets were amplified using primers Olig2F and Olig2R, additional primer Olig2.6F, Stat3R, GfapR were added to the reaction. (C) Primers Stat3R and GfapR are inhibitory to all the tested proofreading DNA polymerases. Primers pBSIIF and pBSIIR were used to amplify the entire plasmid pBlueScript II KS (−). Adding the additional primer Stat3R or GfapR substantially reduced the PCR yield using the proofreading DNA polymerases such as Phusion, Q5, Cobuddy, PS, PSGXL and PfuFly. Arrowheads indicate target DNA fragments.
