Uricolytic enzymes in liver of the Dipnoan Protopterus aethiopicus.
The enzymes uricase, allantoinase, and allantoicase have been measured in liver preparations of the African lungfish Protopterus aethiopicus. The levels for these enzymes in lungfish liver suggest that the amount of urea formed in vivo in Protopterus via a uricolytic pathway may be greater than that derived via the Ornithine-urea cycle. The operation of a "purine cycle" in lungfish liver is proposed.
D002816:Chordata, Nonvertebrate; D008099:Liver / Q000201:enzymology* / Q000378:metabolism; D011687:Purines / Q000378:metabolism; D014503:Urate Oxidase / Q000032:analysis*; D014508:Urea / Q000096:biosynthesis*; D014512:Ureohydrolases / Q000032:analysis*
D011687:Purines; D014508:Urea; D014503:Urate Oxidase; D014512:Ureohydrolases