Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
PYD2 encodes 5,6-dihydropyrimidine amidohydrolase, which participates in anovel fungal catabolic pathway
Autore:
Gojkovic, Z; Jahnke, K; Schnackerz, KD; Piskur, J;
Indirizzi:
Tech Univ Denmark, Dept Microbiol, DK-2800 Lyngby, Denmark Tech Univ Denmark Lyngby Denmark DK-2800 robiol, DK-2800 Lyngby, Denmark Univ Copenhagen, Dept Genet, Inst Mol Biol, DK-1353 Copenhagen K, Denmark Univ Copenhagen Copenhagen Denmark K Biol, DK-1353 Copenhagen K, Denmark Univ Wurzburg, Theodor Boveri Inst Biowissensch, D-97074 Wurzburg, GermanyUniv Wurzburg Wurzburg Germany D-97074 sensch, D-97074 Wurzburg, Germany
Titolo Testata:
JOURNAL OF MOLECULAR BIOLOGY
fascicolo: 4, volume: 295, anno: 2000,
pagine: 1073 - 1087
SICI:
0022-2836(20000128)295:4<1073:PE5AWP>2.0.ZU;2-B
Fonte:
ISI
Lingua:
ENG
Soggetto:
SACCHAROMYCES-CEREVISIAE; D-HYDANTOINASE; PYRIMIDINE CATABOLISM; BETA-ALANINE; AMINO-ACIDS; RAT-LIVER; GENE; YEAST; DIHYDROPYRIMIDINASE; PURIFICATION;
Keywords:
pyrimidines; catabolism; Saccharomyces kluyveri; dihydropyrimidinase; enzyme evolution;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
56
Recensione:
Indirizzi per estratti:
Indirizzo: Piskur, J Tech Univ Denmark, Dept Microbiol, Bldg 301, DK-2800 Lyngby, Denmark Tech Univ Denmark Bldg 301 Lyngby Denmark DK-2800 ngby, Denmark
Citazione:
Z. Gojkovic et al., "PYD2 encodes 5,6-dihydropyrimidine amidohydrolase, which participates in anovel fungal catabolic pathway", J MOL BIOL, 295(4), 2000, pp. 1073-1087

Abstract

Most fungi cannot use pyrimidines or their degradation products as the sole nitrogen source. Previously, we screened several yeasts for their abilityto catabolise pyrimidines. One of them, Saccharomyces kluyveri, was able to degrade the majority of pyrimidines. Here, a series of molecular techniques have been modified to clone pyrimidine catabolic genes, study their expression and purify the corresponding enzymes from this yeast. The pyd2-1 mutant which lacked the 5,6-dihydropyrimidine amidohydrolase (DHPase) activity, was transformed with wild-type S. kluyveri genomic library. The complementing plasmid contained the full sequence of the PYD2 gene, which exhibited a high level of homology with mammalian DHPases and bacterial hydantoinases. The organisation of PYD2 showed a couple of specific features. The 542-codons open reading frame was interrupted by a 63 bp intron, which does not contain the Saccharomyces cerevisiae branch-point sequence, and the transcripts contained a long 5' untranslated leader with five or six AUG codons. The derived amino acid sequence showed similarities with dihydroorotases, allantoinases and uricases from various organisms. Surprisingly, the URA4 genefrom S. cerevisiae, which encodes dihydroorotase, shows greater similarityto PYD2 and other catabolic enzymes than to dihydroorotases from several other non-fungal organisms. The S. kluyveri DHPase was purified to homogeneity and sequencing of the N-terminal region revealed that the purified enzyme corresponds to the PYD2 gene product. The enzyme is a tetramer, likely consisting of similar if not identical subunits each With a molecular mass of59 kDa. The S. kluyveri DHPase was capable of catalysing both dihydrouracil and dihydrothymine degradation, presumably by the same reaction mechanismas that described for mammalian DHPase. On the other hand, the regulation of the yeast PYD2 gene and DHPase seem to be different from that in other organisms. DHPase activity and Northern analysis demonstrated that PYD2 expression is inducible by dihydrouracil, though not by uracil. Apparently, dihydrouracil and DHPase represent an important regulatory checkpoint of the pyrimidine catabolic pathway in S. kluyveri. (C) 2000 Academic Press.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 05/12/20 alle ore 23:27:28