What is PCR?
The PCR full form is Polymerase Chain Reaction, it is a reaction, and is used to produce multiple copies of s gene or DNA of interest. This method is used in labs to produce billions of copies of the desired gene or DNA for research, therapeutic and diagnostic purposes. In 1983, this PCR was invented by Kary Mullis. Generally, PCR requires a DNA primer designed for the DNA template and DNA polymerase, alternatively a thermostable DNA polymerase. Here, for generating a billion copies of DNA, the reaction chain is repeated multiple times in this Polymerase Chain Reaction.
Steps involved in Polymerase Chain reaction:
Here, each cycle of the Polymerase Chain reaction involves and undergoes three essential steps, and they are illustrated in detail.
In PCR the primitive step is denaturation, where Denaturation is required to separate the double-stranded DNA sample. It is achieved at 94-98 ℃ for about 20-30 seconds. It breaks into multiple pieces of hydrogen bonds present between base pairs. This process leads to the formation of single strands of DNA.
Here the second procedure for PCR full form is Polymerase Chain Reaction is Annealing of the primer. Here the reaction temperature is lowered to let the complementary base pairing between the primer and also the complementary part of the single strands of the DNA template simultaneously. To achieve this there needs a proper temperature to be maintained in to let highly specific and proper primer hybridization. After this, DNA polymerase binds to the template-primer hybrid and starts the DNA synthesis.
So, the final process is Extension, for this purpose a thermostable DNA polymerase is used. Moreover, Taq polymerase is basically used for this purpose. It is achieved at a temperature of 75-80 ℃ (72℃). The DNA polymerase adds nucleotides in the 5-inch -3 inch direction and synthesizes the complementary strand of the DNA template.