Adenine chemical structure
Adenine is one of the nucleobase or basic molecules which form DNA and RNA. They are usually called Nitrogenous bases in genetics.
In DNA, adenine sticks to thymine with two hydrogen bonds to help in making the nucleic acid structures stronger. In RNA, which is used in the cytoplasm for protein synthesis, adenine sticks to uracil.
Adenine was sometimes called Vitamin B4, but no longer. However, two B vitamins, niacin and riboflavin, bind with adenine to form the essential cofactors NAD and FAD respectively.
Some think that, at the origin of life on Earth, the first adenine was formed by the polymerization (joining) of five hydrogen cyanide (HCN) molecules. This is not generally accepted.
Images for kids
Adenine on Crick and Watson's DNA molecular model, 1953. The picture is shown upside down compared to most modern drawings of adenine, such as those used in this article.