guanine

American  

[gwah-neen] / ˈgwɑ nin /

noun

Biochemistry.

1. a purine base, C 5 H 5 N 5 O, that is a fundamental constituent of DNA and RNA, in which it forms base pairs with cytosine. G

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guanine British  

/ ˈɡuːəˌniːn, ˈɡwɑːniːn /

noun

1. a white almost insoluble compound: one of the purine bases in nucleic acids. Formula: C 5 H 5 N 5 O

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guanine Scientific  

/ gwä′nēn′ /

1. A purine base that is a component of DNA and RNA, forming a base pair with cytosine. It also occurs in guano, fish scales, sugar beets, and other natural materials. Chemical formula: C ₅ H ₅ ON ₅ .

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Etymology

Origin of guanine

guan(o) + -ine ²

Example Sentences

Importantly they also discovered all five nitrogenous bases — adenine, guanine, cytosine, thymine, and uracil — that are necessary to build DNA and RNA.

From Salon • Jan. 30, 2025

These include 14 of the 20 amino acids that life on Earth uses to build proteins and all four of the ring-shaped molecules that make up DNA - adenine, guanine, cytosine and thymine.

From BBC • Jan. 29, 2025

Nucleotides are composed of three distinctive parts: a sugar molecule, a phosphate group and one of the four nucleobases adenine, thymine, guanine and cytosine.

From Science Daily • Mar. 8, 2024

Huntington’s is a hereditary neurodegenerative disease caused by excess repetitions of three building blocks of DNA — cytosine, adenine, and guanine — on a gene called huntingtin.

From New York Times • May 23, 2023

Three strong hydrogen bonds can be drawn between guanine and cytosine. make the two types of base pairs identical in shape.

From "Double Helix" by James D. Watson