Xenopus allantoicase: molecular cloning, enzymatic activity and developmental expression.
Allantoicase is one of the enzymes of the purine degradation pathway and, interestingly, it appears to be lost, together with uricase and allantoinase, during mammalian evolution. Only allantoicases from the ascomycetes S. pombe, S. cerevisiae, and N. crassa have already been cloned, although the activity has been reported also in fishes and amphibians. By screening a cDNA expression library of Xenopus liver, we have cloned a 1491-bp-length cDNA coding for a 389 amino acid protein that shows an high similarity with the enzyme allantoicase. We have found that allantoicase mRNA is abundantly expressed in kidney and liver, but at much lower level is also present in brain, testis, intestine, and lung. We have detected enzymatic activity in crude extract from kidney, liver, and lung; we have also determined kinetic parameters (K(m) = 8.44 mM, V(max) = 6. 94 micromol min(-1) per mg protein) in kidney. During embryo development, we have detected allantoicase transcript and activity starting from 1 and 5 days after fertilization, respectively.
Vigetti
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Dipartimento di Biologia Strutturale e Funzionale, Università degli Studi dell'Insubria, Via J. H. Dunant 3, Varese, I-21100, Italy.
Monetti
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Pollegioni
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Taramelli
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Bernardini
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D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003605:D-Amino-Acid Oxidase / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D007700:Kinetics; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014512:Ureohydrolases / Q000737:chemistry / Q000235:genetics*; D014981:Xenopus / Q000196:embryology / Q000378:metabolism*
D012333:RNA, Messenger; D003605:D-Amino-Acid Oxidase; D014512:Ureohydrolases; C019658:allantoicase