Property comparison of recombinant amphibian and mammalian allantoicases.
Allantoicase is an enzyme involved in uric acid degradation. Although it is commonly accepted that allantoicase is lost in mammals, birds and reptiles, we have recently identified its transcripts in mice and humans. The mouse mRNA seems capable of encoding a functional allantoicase, therefore we expressed the Xenopus and mouse allantoicases (MAlc and XAlc, respectively) in Escherichia coli and characterized the recombinant enzymes. The two recombinant allantoicases show a similar temperature and pH stability but, although XAlc and MAlc share a 54% amino acid identity, they differ in sensitivity to bivalent cations, in substrate affinity and in the level of expression in tissues (as revealed by means of Western blot analysis). We propose that the loss of allantoicase activity in mouse is due to a low substrate affinity and to a reduced expression level of the enzyme.
Vigetti
Davide
D
Dipartimento di Biologia Strutturale e Funzionale, Universitá degli Studi dell'Insubria, Via J.H. Dunant 3, 21100, Varese, Italy.
Pollegioni
Loredano
L
Monetti
Claudio
C
Prati
Mariangela
M
Bernardini
Giovanni
G
Gornati
Rosalba
R
D000595:Amino Acid Sequence; D000818:Animals; D002413:Cations, Divalent / Q000494:pharmacology; D004795:Enzyme Stability; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D051379:Mice; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D014508:Urea / Q000031:analogs & derivatives* / Q000378:metabolism; D014512:Ureohydrolases / Q000235:genetics / Q000378:metabolism*; D014981:Xenopus
D002413:Cations, Divalent; D011994:Recombinant Proteins; C024081:allantoic acid; D014508:Urea; D014512:Ureohydrolases; C019658:allantoicase