Peroxiredoxins: guardians against oxidative stress and modulators of peroxide signaling

Abstract

Peroxiredoxins (Prxs) are a ubiquitous family of cysteine-dependent peroxidase enzymes that play dominant roles in regulating peroxide levels within cells. These enzymes, often present at high levels and capable of rapidly clearing peroxides, display a remarkable array of variations in their oligomeric states and susceptibility to regulation by hyperoxidative inactivation and other post-translational modifications. Key conserved residues within the active site promote catalysis by stabilizing the transition state required for transferring the terminal oxygen of hydroperoxides to the active site (peroxidatic) cysteine residue. Extensive investigations continue to expand our understanding of the scope of their importance as well as the structures and forces at play within these critical defense and regulatory enzymes.

The Roles of Mitochondrial Reactive Oxygen Species in Cellular Signaling and Stress Response in Plants

“…Exceptions, however, can be found in thiols of a small group of proteins that have been found enriched in mitochondria (Riemer et al, 2015). Particularly interesting are the thiol peroxidases, which have been recognized as among the most H 2 O 2 -reactive thiols in cells (Perkins et al, 2015) and are key players in H 2 O 2 detoxification in plants (Dietz, 2011). With PrxII F and a GPX-like protein, two thiol peroxidases have so far been found in plant mitochondria (Finkemeier et al, 2005;Navrot et al, 2006).…”

Aerobic training reduces oxidative stress in skeletal muscle of rats exposed to air pollution and supplemented with chromium picolinate

“…Likely, CAT activity did not exhibit changes due to the action of other antioxidant mechanisms in skeletal muscle that neutralize hydrogen peroxide, such as glutathione peroxidase (GPx) and peroxiredoxins. Endurance exercise promotes an increase of 20-177% in GPx activity and peroxiredoxins are constitutively secreted from the skeletal muscle, becoming more abundant than CAT and GPx [47][48][49].…”

Monitoring yeast mitochondria with peroxiredoxin-based redox probes: the influence of oxygen and glucose availability

“…Although H 2 O 2 is the predominant substrate, 2-Cys Prxs can also reduce other kinds of peroxides with varied efficiency, including peroxynitrite and organic hydroperoxides. Prxs are reduced via NADPH-dependent systems [8]. Therefore, Prx-based probes in effect should monitor the balance between O 2 -dependent peroxide generation and nutrient-dependent NADPH generation (figure 1).…”