TopTaq DNA Polymerase is a recombinant 94 kDa thermostable DNA Polymerase. TopTaq DNA Polymerase has been developed by QIAGEN to provide highly reliable end-point PCR with unrivaled ease of use. Until the development of the TopTaq PCR system, all PCR enzymes required storage at –20°C; however, due to the unique proprietary TopTaq Stabilizer contained in the enzyme storage buffer, TopTaq DNA Polymerase is the first PCR kit that can be stored at 4°C.
TopTaq DNA Polymerase, in combination with the innovative TopTaq PCR Buffer, facilitates amplification of specific PCR products by providing a high ratio of specific-to-nonspecific primer binding. Owing to a uniquely balanced combination of KCl and (NH4)2SO4, the PCR buffer provides stringent primer-annealing conditions over a wider range of annealing temperatures and Mg2+ concentrations than conventional PCR buffers (see figure " Increased specificity of primer annealing"). The need to optimize PCR by varying the annealing temperature or the Mg2+ concentration is dramatically reduced, or often not required. Thus, TopTaq DNA Polymerase provides the same reliability and specificity as Taq DNA Polymerase and additionally offers improved performance in some PCR systems — resulting in higher yields of PCR products (see figure " High yields of PCR product without optimization").
TopTaq Stabilizer binds to TopTaq DNA Polymerase at 4°C and room temperature, preventing polymerase denaturation during long-term storage. Template DNA and primers are also prevented from binding to the polymerase at low temperature. During the initial denaturation step, the TopTaq Stabilizer dissociates from the polymerase without compromising polymerase activity (see figure " Stabilization at 4°C").
For enhanced convenience, TopTaq DNA Polymerase is supplied with CoralLoad Concentrate. CoralLoad Concentrate contains a gel-loading reagent and two gel-tracking dyes. This unique reagent improves pipetting visibility and facilitates estimation of DNA migration distance and optimization of agarose gel run time. When using CoralLoad Concentrate, PCR products can be directly loaded onto an agarose gel without prior addition of loading buffer (see figure " Convenient CoralLoad Concentrate").
Optimized protocol and buffer
With its balanced potassium and ammonium ions, the unique PCR Buffer, used in combination with TopTaq DNA Polymerase, promotes specific primer–template annealing and simultaneously reduces nonspecific annealing. Maximum yields of specific products are obtained even when using low template amounts.The unique buffer formulation and single preoptimized protocol eliminate the need for optimization of experimental parameters for individual-primer template systems, saving time and costs. High yields of specific amplification product are achieved, even when amplifying a range of fragments of different sizes using the same Mg2+ concentration and annealing temperature (see figure " High PCR product yields without optimization").
This innovative PCR additive facilitates amplification of difficult templates by modifying the melting behavior of DNA. Use of this unique reagent will often enable or improve suboptimal PCR. Unlike DMSO and other PCR additives, Q-Solution is used at a defined working concentration with any primer-template system and is not toxic.