The stereospecific oxidative degradation of uric acid to (S)-allantoin was recently shown to proceed via three enzymatic steps. The final conversion is a decarboxylation of the unstable intermediate 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline (OHCU) and is catalyzed by OHCU decarboxylase. Here we present the structures of Klebsiella pneumoniae OHCU decarboxylase in unliganded form and with bo...

The sensitivity of rice to salt stress greatly depends on growth stages, organ types and cultivars. Especially, the roots of young rice seedlings are highly salt-sensitive organs that limit plant growth, even under mild soil salinity conditions. In an attempt to identify metabolic markers of rice roots responding to salt stress, metabolite profiling was performed by ¹H-NMR spectroscopy in 38 ri...

We demonstrate the presence of an alternate metabolic pathway for urea synthesis in Aedes aegypti mosquitoes that converts uric acid to urea via an amphibian-like uricolytic pathway. For these studies, female mosquitoes were fed a sucrose solution containing (15)NH4Cl, [5-(15)N]-glutamine, [(15)N]-proline, allantoin, or allantoic acid. At 24 h after feeding, the feces were collected and analyze...

Rice snails are one of the pests that have potential to cause high losses rice plants. snail mucus contains glycosaminoglycans, proteoglycans, glycoprotein enzymes, copper peptides, metal ions, collagen, elastin, glycolic acid, allantoin, antimicrobial peptides and vitamin C. Vitamin C or ascorbic acid is vitamins needed by body functions as a help process in body's metabolism. To determine lev...

Urate oxidase is a peroxisomal enzyme with four equal subunits that convert uric acid to allantoin, more soluble metabolite for excretion. The usage of uricase as drug in medicine treat hyperuricemia. Many microorganisms have been used production such Streptomyces exfoliates, Pseudomonas aeruginosa, and Aspergillus flavus. In this study, soil samples were collected then cultured screening mediu...

Methylene blue oxidizes uric acid to allantoin in vitro, analogous to the reaction between uric acid and phosphotungstate, although the rate is considerably slower. The reaction requires oxygen and produces hydrogen peroxide. As little as 10 micromol of methylene blue per liter in a serum sample will produce a measurable difference in the apparent uric acid concentration within 4 h at room temp...