orotic acid monohydrate

Orotic acid monohydrate is an intermediate product in pyrimidine metabolism.

5-Fluoroorotic acid (monohydrate) (5-Fluorouracil-6-carboxylic acid Mono(hydrate); 5-FOA) is employed to detect the expression of the URA3 gene in yeast molecular genetic constructs. Yeast possessing an active URA3 gene (which encodes orotidine-5'-monophosphate decarboxylase) convert 5-FOA into 5-fluorodeoxyuridine, a substance toxic to cells. Yeast strains with mutations in the URA3 gene that confer resistance can grow in the presence of 5-FOA if uracil is added to the medium.

Orotic acid-13C,15N2 (monohydrate) is a marker used in the routine newborn screening for abnormalities in the urea cycle. Orotic acid can induce hepatic steatosis and liver enlargement in rats.