Peroxiredoxin 1 (Prx1) is a dual-function enzyme by possessing Cys-independent catalase-like activity. | Academic Article individual record
abstract

Peroxiredoxin (Prx) was previously known as a Cys-dependent thioredoxin. However, we unexpectedly observed that Prx1 from the green spotted puffer fish Tetraodon nigroviridis (TnPrx1) was able to reduce H2O2 in a manner independent of Cys peroxidation and reductants. This study aimed to validate a novel function for Prx1, delineate the biochemical features and explore its antioxidant role in cells. We have confirmed that Prx1 from the puffer fish and humans truly possesses a catalase (CAT)-like activity that is independent of Cys residues and reductants, but dependent on iron. We have identified that the GVL motif was essential to the CAT-like activity of Prx1, but not to the Cys-dependent thioredoxin peroxidase (POX) activity, and generated mutants lacking POX and/or CAT-like activities for individual functional validation. We discovered that the TnPrx1 POX and CAT-like activities possessed different kinetic features in the reduction of H2O2 The overexpression of wild-type TnPrx1 and mutants differentially regulated the intracellular levels of reactive oxygen species (ROS) and the phosphorylation of p38 in HEK-293T cells treated with H2O2 Prx1 is a dual-function enzyme by acting as POX and CAT with varied affinities towards ROS. This study extends our knowledge on Prx1 and provides new opportunities to further study the biological roles of this family of antioxidants.

authors
author list (cited authors)
Sun, C., Dong, W., Shao, T., Li, J., Zhao, J., Nie, L. i., ... Shao, J.
publication date
2017
publisher
published in
keywords
  • Tetraodontiformes
  • Recombinant Fusion Proteins
  • P38 Mitogen-Activated Protein Kinases
  • Catalase-like Activity
  • Protein Conformation
  • Substrate Specificity
  • Animals
  • Reactive Oxygen Species
  • Amino Acid Substitution
  • Peroxiredoxins
  • Mutation
  • Humans
  • Peroxiredoxin 1 (prx1)
  • Models, Molecular
  • RNA Interference
  • HEK293 Cells
  • Binding Sites
  • Phosphorylation
  • Ros
  • Puffer Fish
  • Fish Proteins
  • Recombinant Proteins
  • Biocatalysis
  • Hydrogen Peroxide
  • Protein Processing, Post-Translational
  • Mutagenesis, Site-Directed
  • Cysteine
altmetric score

0.5

citation count

9