Tags

Type your tag names separated by a space and hit enter

Disulfide biochemistry in 2-cys peroxiredoxin: requirement of Glu50 and Arg146 for the reduction of yeast Tsa1 by thioredoxin.
J Mol Biol. 2012 Nov 23; 424(1-2):28-41.JM

Abstract

2-Cys peroxiredoxin (Prx) enzymes are ubiquitously distributed peroxidases that make use of a peroxidatic cysteine (Cys(P)) to decompose hydroperoxides. A disulfide bond is generated as a consequence of the partial unfolding of the α-helix that contains Cys(P). Therefore, during its catalytic cycle, 2-Cys Prx alternates between two states, locally unfolded and fully folded. Tsa1 (thiol-specific antioxidant protein 1 from yeast) is by far the most abundant Cys-based peroxidase in Saccharomyces cerevisiae. In this work, we present the crystallographic structure at 2.8Å resolution of Tsa1(C47S) in the decameric form [(α(2))(5)] with a DTT molecule bound to the active site, representing one of the few available reports of a 2-Cys Prx (AhpC-Prx1 subfamily) (AhpC, alkyl hydroperoxide reductase subunit C) structure that incorporates a ligand. The analysis of the Tsa1(C47S) structure indicated that Glu50 and Arg146 participate in the stabilization of the Cys(P) α-helix. As a consequence, we raised the hypothesis that Glu50 and Arg146 might be relevant to the Cys(P) reactivity. Therefore, Tsa1(E50A) and Tsa1(R146Q) mutants were generated and were still able to decompose hydrogen peroxide, presenting a second-order rate constant in the range of 10(6)M(-1)s(-1). Remarkably, although Tsa1(E50A) and Tsa1(R146Q) were efficiently reduced by the low-molecular-weight reductant DTT, these mutants displayed only marginal thioredoxin (Trx)-dependent peroxidase activity, indicating that Glu50 and Arg146 are important for the Tsa1-Trx interaction. These results may impact the comprehension of downstream events of signaling pathways that are triggered by the oxidation of critical Cys residues, such as Trx.

Authors+Show Affiliations

Departamento de Biologia, Universidade Estadual Paulista Júlio de Mesquita Filho, Campus do Litoral Paulista São Vicente, São Paulo, Brazil.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

22985967

Citation

Tairum, Carlos A., et al. "Disulfide Biochemistry in 2-cys Peroxiredoxin: Requirement of Glu50 and Arg146 for the Reduction of Yeast Tsa1 By Thioredoxin." Journal of Molecular Biology, vol. 424, no. 1-2, 2012, pp. 28-41.
Tairum CA, de Oliveira MA, Horta BB, et al. Disulfide biochemistry in 2-cys peroxiredoxin: requirement of Glu50 and Arg146 for the reduction of yeast Tsa1 by thioredoxin. J Mol Biol. 2012;424(1-2):28-41.
Tairum, C. A., de Oliveira, M. A., Horta, B. B., Zara, F. J., & Netto, L. E. (2012). Disulfide biochemistry in 2-cys peroxiredoxin: requirement of Glu50 and Arg146 for the reduction of yeast Tsa1 by thioredoxin. Journal of Molecular Biology, 424(1-2), 28-41. https://doi.org/10.1016/j.jmb.2012.09.008
Tairum CA, et al. Disulfide Biochemistry in 2-cys Peroxiredoxin: Requirement of Glu50 and Arg146 for the Reduction of Yeast Tsa1 By Thioredoxin. J Mol Biol. 2012 Nov 23;424(1-2):28-41. PubMed PMID: 22985967.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Disulfide biochemistry in 2-cys peroxiredoxin: requirement of Glu50 and Arg146 for the reduction of yeast Tsa1 by thioredoxin. AU - Tairum,Carlos A,Jr AU - de Oliveira,Marcos A, AU - Horta,Bruno B, AU - Zara,Fernando J, AU - Netto,Luis E S, Y1 - 2012/09/15/ PY - 2012/02/23/received PY - 2012/09/01/revised PY - 2012/09/07/accepted PY - 2012/9/19/entrez PY - 2012/9/19/pubmed PY - 2013/1/9/medline SP - 28 EP - 41 JF - Journal of molecular biology JO - J Mol Biol VL - 424 IS - 1-2 N2 - 2-Cys peroxiredoxin (Prx) enzymes are ubiquitously distributed peroxidases that make use of a peroxidatic cysteine (Cys(P)) to decompose hydroperoxides. A disulfide bond is generated as a consequence of the partial unfolding of the α-helix that contains Cys(P). Therefore, during its catalytic cycle, 2-Cys Prx alternates between two states, locally unfolded and fully folded. Tsa1 (thiol-specific antioxidant protein 1 from yeast) is by far the most abundant Cys-based peroxidase in Saccharomyces cerevisiae. In this work, we present the crystallographic structure at 2.8Å resolution of Tsa1(C47S) in the decameric form [(α(2))(5)] with a DTT molecule bound to the active site, representing one of the few available reports of a 2-Cys Prx (AhpC-Prx1 subfamily) (AhpC, alkyl hydroperoxide reductase subunit C) structure that incorporates a ligand. The analysis of the Tsa1(C47S) structure indicated that Glu50 and Arg146 participate in the stabilization of the Cys(P) α-helix. As a consequence, we raised the hypothesis that Glu50 and Arg146 might be relevant to the Cys(P) reactivity. Therefore, Tsa1(E50A) and Tsa1(R146Q) mutants were generated and were still able to decompose hydrogen peroxide, presenting a second-order rate constant in the range of 10(6)M(-1)s(-1). Remarkably, although Tsa1(E50A) and Tsa1(R146Q) were efficiently reduced by the low-molecular-weight reductant DTT, these mutants displayed only marginal thioredoxin (Trx)-dependent peroxidase activity, indicating that Glu50 and Arg146 are important for the Tsa1-Trx interaction. These results may impact the comprehension of downstream events of signaling pathways that are triggered by the oxidation of critical Cys residues, such as Trx. SN - 1089-8638 UR - https://www.unboundmedicine.com/medline/citation/22985967/Disulfide_biochemistry_in_2_cys_peroxiredoxin:_requirement_of_Glu50_and_Arg146_for_the_reduction_of_yeast_Tsa1_by_thioredoxin_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0022-2836(12)00745-0 DB - PRIME DP - Unbound Medicine ER -