Magnesium is required as a co-factor for thermostable DNA polymerase. Taq polymerase is a magnesium-dependent enzyme and determining the optimum concentration to use is critical to the success of the PCR reaction.
Why do you need buffer in PCR?
Isopropanol precipitation of DNA and treatment of DNA pellets with 70% ethanol is usually effective in removing traces of contaminants from the DNA sample. PCR buffer is necessary to create optimal conditions for activity of Taq DNA polymerase. Buffers often contain Tris-Hcl, KCl, and sometimes MgCl2.
What is the role of dNTPs in PCR?
Deoxynucleoside triphosphates (dNTPs) dNTPs consist of four basic nucleotides—dATP, dCTP, dGTP, and dTTP—as building blocks of new DNA strands. However, dNTPs exceeding optimal concentrations can inhibit PCR.