Sanger process
The sequencing reaction
DNA sequencing involves making copies in the original DNA sequence; the reaction uses the inspiration of DNA and an enzyme called DNA polymerase to provide new bases to a growing DNA chain. However, this reaction is set up in order that it doesn't work all the moment - we don't want a perfect copy of our DNA.
Initial, the two strands of the DNA in the pUC clones are separated. Next, a short piece of DNA termed a primer is added. The primer will bind specifically to a DNA sequence in the pUC molecule. What's more, it serves as a starting point for developing a new DNA chain. New blocks of the DNA chain are added as well as DNA polymerase. If this have been all, the reaction would copy a fresh chain until it stopped.
The main element to all DNA sequencing and the development that gave Fred Sanger the second Nobel Prize was the actual dideoxy base. DNA is called deoxyribonucleic acid solution because the ribose sugar section of the molecule is lacking an oxygen atom within normal ribose. Dideoxy bases lack a second oxygen atom that's needed is to extend the growing DNA string. This means that when some sort of dideoxy base is incorporated in a DNA molecule, the chain prevents or terminates.
The reactions are set up so that there are a mix of 'normal' along with dideoxy bases. At any placement, either a normal base will be added, so the chain can carry on and grow, or a dideoxy base will be added, so the chain ends. After many cycles of burning, all the possible chain-termination compounds are produced: the reaction features stopped at every base.
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