Increasing occurrences and functional roles for high energy purine-pyrimidine base-pairs in nucleic acids.
There are a growing number of studies reporting the observation of purine-pyrimidine base-pairs that are seldom observed in unmodified nucleic acids because they entail the loss of energetically favorable interactions or require energetically costly base ionization or tautomerization. These high energy purine-pyrimidine base-pairs include G•C(+) and A•T Hoogsteen base-pairs, which entail ∼180° rotation of the purine base in a Watson-Crick base-pair, protonation of cytosine N3, and constriction of the C1'-C1' distance by ∼2.5Å. Other high energy pure-pyrimidine base-pairs include G•T, G•U, and A•C mispairs that adopt Watson-Crick like geometry through either base ionization or tautomerization. Although difficult to detect and characterize using biophysical methods, high energy purine-pyrimidine base-pairs appear to be more common than once thought. They further expand the structural and functional diversity of canonical and non-canonical nucleic acid base-pairs.
Duke Scholars
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- Pyrimidines
- Purines
- Nucleic Acid Conformation
- Models, Molecular
- Isomerism
- Humans
- DNA
- Biophysics
- Base Pairing
- Animals
Citation
Published In
DOI
EISSN
Publication Date
Volume
Start / End Page
Location
Related Subject Headings
- Pyrimidines
- Purines
- Nucleic Acid Conformation
- Models, Molecular
- Isomerism
- Humans
- DNA
- Biophysics
- Base Pairing
- Animals