DNA
DNA is made up by Sugar, Phosphate Group and Nitrogenous Base
Components:
Sugar
5-carbon deoxyribose sugar, carbon labelled from 1' to 5' clockwise
Phosphate Group (PO4)
Attached on 5' carbon of deoxyribose sugar with easter bond
Nitrogenous Base
Attached on 1' carbon of deoxyribose sugar with glycosidic bond.
Sugar
Different from Ribose, a monosaccharide, deoxyribose doesn't have the OH hydroxyl group on 2' carbon
The application around DNA's monosaccharide structure is further applied on Sanger's sequencing.
Sanger's Sequencing
1. Template DNA is sent to 4 tubes, each tube has a primer, dNTP, DNA Polymerase
2. We put in little concentration of radiolabelled ddNTP, the nucleotides that stops polymerase from adding more nucleotides
3. The length could be obtained from electrophoresis
put DNA molecules in a capillary tube and applie eletric charge to it. The same negative charge repels DNA and force it to "swim" in the gel. The shorter DNA fragments swims faster and the longer ones swims slower. As they reach to the terminal, we could detect the radiograph and knows which NTP is at where.
In this case, scientists uses ddNTP tha has no oxyten on 2' and 3' OH groups, therefore the ddNTP can not have reaction between it's Oxygen and the Phosphate group, so the polymerization stopped.
Nitrogeneous bases
Pyramidines
- Has Single Ring
Purine
- Has Double Ring
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