B IO C H E M IS T R Y PE A R L S
The most stable DNA structure is formed when two polynucleotide
chains are joined by hydrogen bonding between the side chain
bases. The base pairing is specific in that adenine pairs with
thymine and guanine pairs with cytosine (A-T; G-C)
Experimentally, the double helix can be separated, or denatured, by
increasing the temperature to well above 50°C (122°F); if the
temperature is carefully decreased, renaturation occurs when the
base pairs reform.
Ribavirin is a purine nucleoside analog exhibiting in vitro antiviral
activity against a broad spectrum of DNA and RNA viruses,
including clinical efficacy against both influenza A and B virus.
Ribavirin seems to cause mutagenic changes to RNA viruses, with
ribavirin being inserted into newly synthesized copies of their
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Gilbert BE, Knight V. Biochemistry and clinical applications of ribavirin.
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Maag D, Castro C, Hong Z, et al. Hepatitis C virus RNA-dependent RNA poly-
merase (NS5B) as a mediator of the antiviral activity of ribavirin. J Biol Chem