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Guanine (Molecule of the Month for August 2019)

Nucleobase, DNA

Guanine is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine (uracil in RNA). In DNA, guanine is paired with cytosine. The guanine nucleoside is called guanosine.

Guanine binds to cytosine through three hydrogen bonds. In cytosine, the amino group acts as the hydrogen bond donor and the C-2 carbonyl and the N-3 amine as the hydrogen-bond acceptors. Guanine has the C-6 carbonyl group that acts as the hydrogen bond acceptor, while a group at N-1 and the amino group at C-2 act as the hydrogen bond donors.

Formal Chemical Name (IUPAC)



Picture of Guanine 3D model

click on the picture of  Guanine above to interact
with the 3D model of the
Guanine structure
(this will open a new browser window)

Picture of Guanine

C5 H5 N5 O

Update by Karl Harrison
(Molecule of the Month for August 2019 )

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