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DNA polymerases are a family of enzymes critical for all forms of DNA replication. A DNA polymerase synthesizes a new strand of DNA by extending the 3′ end of an existing nucleotide chain, adding new nucleotides matched to the template strand one at a time. Some DNA polymerases may also have some proofreading ability, removing […]
DNA is a long polymer made from repeating units called nucleotides. The DNA chain is 22 to 26 Ã…ngströms wide (2.2 to 2.6 nanometres), and one nucleotide unit is 3.3 Ã… (0.33 nm) long. Although each individual repeating unit is very small, DNA polymers can be enormous molecules containing millions of nucleotides. For instance, the […]
The double helix is a right-handed spiral. As the DNA strands wind around each other, they leave gaps between each set of phosphate backbones, revealing the sides of the bases inside (see animation). There are two of these grooves twisting around the surface of the double helix: one groove, the major groove, is 22 Ã… […]
Each type of base on one strand forms a bond with just one type of base on the other strand. This is called complementary base pairing. Here, purines form hydrogen bonds to pyrimidines, with A bonding only to T, and C bonding only to G. This arrangement of two nucleotides binding together across the double […]
Molecular biology
Nucleic acid analogues are used in molecular biology for several purposes:
As a tool to detect particular sequences
As a tool with resistance to RNA hydrolysis)
As a tool for another purpose, such as sequencing
Naturally occurring, such as in tRNA
Investigation of the mechanisms used by enzyme, such as an Enzyme inhibitor)
Investigation of possible scenarios of the origin […]
