Biochemistry - Chemical Reactions in Living Cells, Volume 1 - D. Metzler 1980

The Molecules We Are Made Of
Nucleic Acids
Tautomerism and Base Pairing

The formation of two and three Hydrogen Bonds between DNA bases has an interesting connection to Tautomerism. Each base exists predominantly in one specific tautomeric form; however, at any given moment, at least a few bases find themselves in a less stable form. This, in particular, accounts for the occurrence of certain Mutations. For instance, tautomer B in equation (2-5) can no longer pair with thymine, its regular partner, but is instead capable of forming hydrogen bonds with cytosine. If this happens during Gene Replication, it results in an incorrect copy in which one "letter" of METABOLISM/28.html">The Genetic Code has been substituted.



Last update: 06/08/2026

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