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The annealing temperature typically ranges from 50-65°C and depends on the primer's melting temperature (Tm). This allows primers to bind specifically to complementary sequences on the template DNA.
Taq DNA Polymerase (thermostable polymerase from Thermus aquaticus) is the standard enzyme used in PCR. It synthesizes DNA by adding nucleotides to the 3'-OH group of the growing strand.
ddNTPs (dideoxynucleotides) lack a 3'-OH group, causing chain termination when incorporated, generating DNA fragments of different lengths for sequencing.
Restriction enzymes are used in DNA cloning and digestion, not in PCR. PCR requires template DNA, primers, dNTPs, Taq polymerase, and buffer.
Standard PCR typically uses 25-35 cycles to achieve sufficient exponential amplification (2^n copies) without compromising specificity or introducing errors.
Taq polymerase (thermostable DNA polymerase from Thermus aquaticus) synthesizes new DNA strands at 72°C during the extension phase of PCR.
Extension/elongation happens at 72-75°C, the optimal temperature for Taq polymerase to synthesize DNA.
Kary Mullis invented PCR in 1983, a revolutionary technique that earned him the Nobel Prize in Chemistry in 1993.
DNA ligase catalyzes the formation of phosphodiester bonds between adjacent nucleotides, joining DNA fragments.
Restriction endonucleases recognize specific palindromic DNA sequences and cut predictably at these sites.
