Metabolism of the Nucleotide (2-Thio-UMP) of the Antithyroid Drug 2-Thiouracil:

SummaryThe results presented demonstrated that a mixture of rat liver mono- and diphosphokinases metabolized 2-thio-UMP to two substances. One was identified as thio-UTP. The other had some properties similar to thio-UDP but was chromatographically different. The rate of UMP conversion to UDP and UTP by this enzyme system greatly exceeded that of thio-UMP to nucleoside triphosphate. Thio-UMP conversion to thio-UTP demonstrates that pathways are present in animal tissues for the metabolism of 2-thiouracil to 2-thio-UTP. The enzymes involved appear to be identical or very similar to those converting uracil to UTP.