Abstract |
OXP1/YKL215c, an uncharacterized ORF of Saccharomyces cerevisiae, encodes a functional ATP-dependent 5-oxoprolinase of 1286 amino acids. The yeast 5-oxoprolinase activity was demonstrated in vivo by utilization of 5-oxoproline as a source of glutamate and OTC, a 5-oxoproline sulfur analogue, as a source of sulfur in cells overexpressing OXP1. In vitro characterization by expression and purification of the recombinant protein in S. cerevisiae revealed that the enzyme exists and functions as a dimer, and has a K(m) of 159 microM and a V(max) of 3.5 nmol h(-1) microg(-1) protein. The enzyme was found to be functionally separable in two distinct domains. An 'actin-like ATPase motif' could be identified in 5-oxprolinases, and mutation of key residues within this motif led to complete loss in ATPase and 5-oxoprolinase activity of the enzyme. The results are discussed in the light of the previously postulated truncated gamma-glutamyl cycle of yeasts.
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Authors | Akhilesh Kumar, Anand Kumar Bachhawat |
Journal | FEMS yeast research
(FEMS Yeast Res)
Vol. 10
Issue 4
Pg. 394-401
(Jun 2010)
ISSN: 1567-1364 [Electronic] England |
PMID | 20402795
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Recombinant Proteins
- Saccharomyces cerevisiae Proteins
- Glutamic Acid
- Sulfur
- Adenosine Triphosphate
- Pyroglutamate Hydrolase
- Adenosine Triphosphatases
- Pyrrolidonecarboxylic Acid
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Topics |
- Adenosine Triphosphatases
(genetics, metabolism)
- Adenosine Triphosphate
(metabolism)
- Binding Sites
- Dimerization
- Gene Expression
- Glutamic Acid
(metabolism)
- Kinetics
- Models, Molecular
- Protein Binding
- Protein Structure, Tertiary
- Pyroglutamate Hydrolase
(genetics, isolation & purification, metabolism)
- Pyrrolidonecarboxylic Acid
(analogs & derivatives, metabolism)
- Recombinant Proteins
(genetics, isolation & purification, metabolism)
- Saccharomyces cerevisiae
(enzymology, genetics)
- Saccharomyces cerevisiae Proteins
(genetics, isolation & purification, metabolism)
- Sulfur
(metabolism)
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