B-DNA

chemical compound

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Last updated

July 17, 2026

Quick Summary

B-DNA refers to the common, right-handed double helix structure of deoxyribonucleic acid (DNA). DNA is a polymer made of four nucleotides: adenine (A), cytosine (C), guanine (G), and thymine (T). These nucleotides form a double helix, with the sugar-phosphate chains on the outside and the bases on the inside. Adenine always pairs with thymine (A-T) via two hydrogen bonds, and guanine always pairs with cytosine (G-C) via three hydrogen bonds. This complementary base pairing is crucial for DNA's ability to replicate and transmit genetic information. B-DNA makes one full turn approximately every 10 base pairs and has a major and minor groove, which are important for protein interactions.1

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nucleic acid
Chemical structure
B-DNA has two principal grooves, a wide major groove and a narrow minor groove. Many proteins interact in the space of the major groove, where they make sequence-specific contacts with the bases. In addition, a few proteins are known to make contacts via the minor…
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B-DNA has two principal grooves, a wide major groove and a narrow minor groove. Many proteins interact in the space of the major groove, where they make sequence-specific contacts with the bases. In addition, a few proteins are known to make contacts via the minor…
Read More