Gene identification and enzymatic characterization of the initial enzyme in pyrimidine oxidative metabolism, uracil-thymine dehydrogenase.
J Biosci Bioeng
; 137(6): 413-419, 2024 Jun.
Article
in En
| MEDLINE
| ID: mdl-38485553
ABSTRACT
Uracil-thymine dehydrogenase (UTDH), which catalyzes the irreversible oxidation of uracil to barbituric acid in oxidative pyrimidine metabolism, was purified from Rhodococcus erythropolis JCM 3132. The finding of unusual stabilizing conditions (pH 11, in the presence of NADP+ or NADPH) enabled the enzyme purification. The purified enzyme was a heteromer consisting of three different subunits. The enzyme catalyzed oxidation of uracil to barbituric acid with artificial electron acceptors such as methylene blue, phenazine methosulfate, benzoquinone, and α-naphthoquinone; however, NAD+, NADP+, flavin adenine dinucleotide, and flavin mononucleotide did not serve as electron acceptors. The enzyme acted not only on uracil and thymine but also on 5-halogen-substituted uracil and hydroxypyrimidine (pyrimidone), while dihydropyrimidine, which is an intermediate in reductive pyrimidine metabolism, and purine did not serve as substrates. The activity of UTDH was enhanced by cerium ions, and this activation was observed with all combinations of substrates and electron acceptors.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Oxidation-Reduction
/
Pyrimidines
/
Uracil
/
Rhodococcus
Language:
En
Journal:
J Biosci Bioeng
Journal subject:
ENGENHARIA BIOMEDICA
/
MICROBIOLOGIA
Year:
2024
Document type:
Article
Affiliation country:
Japan
Country of publication:
Japan