| Autor: |
Kumar A; Institute of Microbial Technology (CSIR), Chandigarh, India., Bachhawat AK |
| Jazyk: |
angličtina |
| Zdroj: |
FEMS yeast research [FEMS Yeast Res] 2010 Jun; Vol. 10 (4), pp. 394-401. Date of Electronic Publication: 2010 Mar 10. |
| DOI: |
10.1111/j.1567-1364.2010.00619.x |
| Abstrakt: |
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. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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