Orotidine is a nucleoside formed by attaching orotic acid to a ribose ring via a β-N₁- glycosidic bond. It is found in

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

fungi A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

and plants. It was first isolated in 1951 from the fungus '' Neurospora'' by A. Michael Michelson, William Drell, and Herschel K. Mitchell. In humans, orotidine occurs as its 5'-phosphate ( orotidylic acid), which is an intermediate in pyrimidine nucleotide biosynthesis ( cytidine and uridine) that are found in

nucleic acid Nucleic acids are large biomolecules that are crucial in all cells and viruses. They are composed of nucleotides, which are the monomer components: a pentose, 5-carbon sugar, a phosphate group and a nitrogenous base. The two main classes of nuclei ...

s. Orotidine itself is not a component of nucleic acid. Large amounts of orotidine are excreted in the urine of cancer patients treated with 6-azauridine. The symbol commonly used for orotidine is O or Ord.

Notes

{{Reflist Nucleosides Pyrimidinediones Hydroxymethyl compounds