|Gene:||AAH||Accession Number: AT4G20070 (MetaCyc)|
Synonyms: At4g20070, AtAAH
Species: Arabidopsis thaliana col
The cDNA encoding allantoate amidohydrolase was isolated from Arabidopsis thaliana col. The enzyme was initially reported to catalyzes the conversion of allantoate to yield S-ureidoglycolate via a (-)-ureidoglycine [Todd06], but a later study showed that the enzyme catalyzes only the first part - conversion of allantoate to a (-)-ureidoglycine [Werner10]
The function of the gene was confirmed by complementation of Saccharomyces cerevisiae DAL2 mutants, blocked in allantoate degradation. Mutants with T-DNA insertions in AAH, the gene encoding the enzyme, showed normal growth on standard medium, but growth was completely blocked when the sole N source was allantoin. The enzyme was expressed in all tissues indicating a vital role in metabolism. It was proposed that the enzyme is involved in the purine salvage pathway through ureide biosynthesis and degradation [Todd06].
The gene was subsequently cloned, expressed in planta in the form of several StrepII-tagged variants, and highly purified from leaf extracts. The enzyme requires Mn2+ and exists as a homodimer [Werner08].
Molecular Weight of Polypeptide: 56.524 kD (from nucleotide sequence)
Relationship Links: InterPro:IN-FAMILY:IPR001261 , InterPro:IN-FAMILY:IPR002933 , InterPro:IN-FAMILY:IPR010158 , InterPro:IN-FAMILY:IPR011650 , Pfam:IN-FAMILY:PF01546 , Pfam:IN-FAMILY:PF07687 , Prosite:IN-FAMILY:PS00758 , Prosite:IN-FAMILY:PS00759
Enzymatic reaction of: allantoate amidohydrolase
EC Number: 18.104.22.168
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
The reaction is favored in the direction shown.
Werner08: Werner AK, Sparkes IA, Romeis T, Witte CP (2008). "Identification, biochemical characterization, and subcellular localization of allantoate amidohydrolases from Arabidopsis and soybean." Plant Physiol 146(2);418-30. PMID: 18065556
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