PCR Chapter 6 BioRad

PCR

PCR

A technique that uses a series of denaturation, annealing and extension steps to copy or amplify a specific DNA sequence.

Taq polymerase

A thermally stable enzyme used in PCR to amplify a nucleic acid, by adding nucleotides to the growing molecule during extension.

annealing

A PCR step in which the reaction is cooled so the primers can bind to the complementary sequence on the denatured template.

denaturation

A PCR step in which the reaction is heated to break the hydrogen bonds that hold double-stranded DNA together, thus separating DNA into single strands. Temperature is between 92-95 deg C.

extension

A PCR step in which the temperature is set to allow DNA (Taq) polymerase to extend the primer by adding nucleotides complementary to the template sequence.

DNA replication

The common way in which DNA is synthesized. Each of the strands in a double helix acts as a template for a new strand. Hence, after replication, each double helix consists of one old and one new strand.

primer

A short, single-stranded DNA segment that is the necessary starting material for the synthesis of a new DNA strand. For purposes of PCR, the segments are engineered in a laboratory. Also referred to as oligonucleotides. Each PCR reaction requires a forward and reverse one of these to designate the start and end of the target sequence.