A Selenocysteine-Containing Peroxiredoxin from the Strictly Anaerobic Organism Eubacterium acidaminophilum
- 27 June 2001
- journal article
- Published by Walter de Gruyter GmbH in Biological Chemistry
- Vol. 382 (6) , 979-986
- https://doi.org/10.1515/bc.2001.123
Abstract
A strongly [75]Selabeled 22 kDa protein detected previously showed in its Nterminal sequence the highest similarity to the family of thioldependent peroxidases, now called peroxiredoxins. The respective gene prxU was cloned and analyzed. prxU encodes a protein of 203 amino acids (22470 Da) and contains an inframe UGA codon (selenocysteine) at the position of the so far strictly conserved and catalytically active Cys47. The second conserved cysteine present in 2-Cys peroxiredoxins was replaced by alanine. Heterologous expression of the Eubacterium acidaminophilum PrxU as a recombinant selenoprotein in Escherichia coli was not possible. A cysteineencoding mutant gene, prxU47C, containing UGC instead of UGA was strongly expressed. This recombinant PrxU47C mutant protein was purified to homogeneity by its affinity tag, but was not active as a thioldependent peroxidase. The identification of prxU reveals that the limited class of natural selenoproteins may in certain organisms also include isoenzymes of peroxiredoxins, previously only known as nonselenoproteins containing catalytic cysteine residues.Keywords
This publication has 38 references indexed in Scilit:
- Various functions of selenols and thiols in anaerobic Gram‐positive, amino acids‐utilizing bacteriaBioFactors, 1999
- Bacillus subtilis contains multiple Fur homologues: identification of the iron uptake (Fur) and peroxide regulon (PerR) repressorsMolecular Microbiology, 1998
- Crystal structure of a novel human peroxidase enzyme at 2.0 Å resolutionNature Structural & Molecular Biology, 1998
- Roles for the Two Cysteine Residues of AhpC in Catalysis of Peroxide Reduction by Alkyl Hydroperoxide Reductase from Salmonella typhimuriumBiochemistry, 1997
- Complete Genome Sequence of the Methanogenic Archaeon, Methanococcus jannaschii Science, 1996
- The Phylogeny of the Genus Clostridium: Proposal of Five New Genera and Eleven New Species CombinationsInternational Journal of Systematic and Evolutionary Microbiology, 1994
- Cloning and sequencing of thiol-specific antioxidant from mammalian brain: alkyl hydroperoxide reductase and thiol-specific antioxidant define a large family of antioxidant enzymes.Proceedings of the National Academy of Sciences, 1994
- Glycine metabolism in anaerobesAntonie van Leeuwenhoek, 1994
- Interaction of selenoprotein PA and the thioredoxin system, components of the NADPH-dependent reduction of glycine in Eubacterium acidaminophilum and Clostridium litorale [corrected]Journal of Bacteriology, 1991
- A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye bindingAnalytical Biochemistry, 1976