Formation in vitro of Uridine Phosphates from Orotic Acid

Non-utilization of radioactive iodinated uracil, uridine, and orotic acid by animal tissues in vivo.

The formation of cytidine nucleotides and RNA cytosine from orotic acid by the Novikoff tumor in vitro.

The utilization of orotic acid for the formation of RNA ~ uracil has been extensively studied in intact animals, tissue slices, and cell suspensions (reviewed in Refs. 5, 31). The mechanism of the utilization, via the initial conversion of orotic acid to uridine nucleotides and the incorporation of uridine nucleotides into polynucleotides, has been partially described in intact animals (13, 17)...

The formation of uridine diphosphate-glucuronic acid in plants. Uridine diphosphate-glucuronic acid pyrophosphorylase from barley seedlings.

UDP-glucuronic acid pyrophosphorylase was purified approximately 80-fold from barley seedlings by ammonium sulfate fractionation and column chromatography on DEAEcellulose and Sephadex G-100. The partially purified enzyme can be assayed radiochemically in either the forward or reverse direction and has K, values of 0.33 mM and 0.5 mM for n-glucuronic acid l-phosphate and UDP-D-glucuronic acid, ...

Orotic acid in milk.

Other studies in this laboratory (1) drew our attention to the possibility that erotic acid might be concerned with the maintenance of adequate lactation in the rat and with the survival of the young. Since no data were available on the erotic acid content of milk, this study was undertaken. The occurrence of erotic acid as a component of milk has been indicated since 1904, when Biscaro and Bel...

Orotic Acid Feeding

1. The metabolism of 4-[4-14C]androstene-3,17-dione, 4-[4-14C]pregnene-3,20-dione, 5a-[4-14C]androstane-3a,17f8-diol, [4-4C]cholesterol, 7a-hydroxy4-6fi-3H]cholesten3-one, 5fi-[7fi-3H]cholestane-3a,7U-diol and [3H]lithocholic acid was studied in the microsomal fraction of livers from control and orotic acid-treated male rats. 2. As a result of the treatment the orotic acid-fed rats had fatty li...