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

In contrast, her team's findings show that the presence of bicarbonate from dissolved CO₂ changes the reaction to make a milder radical striking only guanine, the G in our four-letter genetic code.

From Science Daily • Nov. 26, 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

The formation of a third hydrogen bond between guanine and cytosine was considered, but rejected because a crystallographic study of guanine hinted that it would be very weak.

From "Double Helix" by James D. Watson