Uricase Assay Kit

Uricase (urate oxidase or urate:oxygen oxidoreductase, EC 1.7.3.3) is a peroxisomal and cytosolic enzyme that catalyzes the oxidation of uric acid to 5-hydroxyisourate, which is subsequently converted non-enzymatically or via accessory enzymes to allantoin, a highly water-soluble compound readily excreted by the kidneys. This enzymatic activity represents a critical step in purine catabolism beyond uric acid formation, and is present in most mammals, fish, amphibians, and many invertebrates, but has been lost through pseudogenization in humans, great apes, and some New World monkeys during evolution. The enzyme functions as a homo-tetramer, requires no cofactors, and directly utilizes molecular oxygen (O₂) while producing hydrogen peroxide (H₂O₂) as a byproduct, situating uricase at the intersection of purine degradation, nitrogen excretion, and oxidative metabolism. The evolutionary loss of functional uricase in hominids results in serum uric acid levels 5–10 times higher than in other mammals, with humans uniquely susceptible to hyperuricemia, gout, and urate-related pathologies, while also potentially benefiting from uric acid′s antioxidant properties—a trade-off that has made uricase a focal point in metabolic disease research and the target of therapeutic enzyme replacement strategies for severe gout and tumor lysis syndrome.

Suitable for the uricase activity quantitation in biological samples such as cell culture, non-human biofluids, cell extracts, and plant tissue extracts.

The Uricase Assay Kit provides a rapid fluorometric method to quantify uricase activity. In this assay, uric acid is enzymatically converted to allantoin, releasing H₂O₂. The resulting H₂O₂ reacts with a specific dye to form a pink colored product. The change in fluorescence intensity at 530/585 nm is directly proportional to the uricase activity in the sample. The linear detection range is 0.3 - 100 U/L Uricase.