Lecture 2: DNA Replication, PCR, Sequencing; Chapter 7
DNA is composed of nucleotides: purines and pyrimidines.
These are nucleotides with either two rings or a single one. The difference is essential to the hydrogen bonding. The structure allows specificity of the structure. A-T and G-C. Specificity is based on how thse molecules are shaped and their ability on making hydrogen bonds. A single hydrogen bond is low energy bond. Many and thousands of hydrogen bonds summoned will become like Velcro which can be extremely strong. NUCLEOTIDES CAN BE POLYMERIZED.
How can you make a polynucleotide?
Dehydration reaction: Remove a water molecule to get subunits. DNA chain has a 5 and 3 prime end. Refers to different carbons on the deoxyribose. 5 prime has a phosphate on it and 3 prime end has a hydroxyl group on it. The way you polymerize the DNA is by taking a precursor nucleotide triphosphate. It has 3 phosphates group on its five prime end. These phosphates group interact with the 3 prime hydroxyl. Two of these phosphates are cleaved off and hydrolyzed to form a new phosphodiester bond between them. DNA forms a double helix?
How do you make sure you get the right nucleotide? The way you do that is the properties of DNA and base pairing of nucleotides. This is a structure DNA as a double helix. In the double helix is the two strands of DNA are compleme...