Suicide Inactivation of Peroxidases and the Challenge of Engineering More Robust Enzymes

Abstract

As the number of industrial applications for proteins continues to expand, the exploitation of protein engineering becomes critical. It is predicted that protein engineering can generate enzymes with new catalytic properties and create desirable, high-value, products at lower production costs. Peroxidases are ubiquitous enzymes that catalyze a variety of oxygen-transfer reactions and are thus potentially useful for industrial and biomedical applications. However, peroxidases are unstable and are readily inactivated by their substrate, hydrogen peroxide. Researchers rely on the powerful tools of molecular biology to improve the stability of these enzymes, either by protecting residues sensitive to oxidation or by devising more efficient intramolecular pathways for free-radical allocation. Here, we discuss the catalytic cycle of peroxidases and the mechanism of the suicide inactivation process to establish a broad knowledge base for future rational protein engineering.

Conditional Expression of 15-Lipoxygenase-1 Inhibits the Selenoenzyme Thioredoxin Reductase

“…However, inhibition of TrxR persisted for 8 h (Fig. 3B), consistent with irreversible, autoinactivation that accompanies lipid peroxidase catalysis (45)(46)(47), or with irreversible inactivation by 4-HNE reported for other enzymes (48) and selenoenzymes (49).…”

Conservation of minimally processed apples using edible coatings made of turnip extract and xanthan gum

“…However, during storage, a trend for a reduction in peroxidase activity was observed. According to Valderrama et al (2002) peroxidases are relatively unstable and susceptible to inactivation in the presence of hydrogen peroxide. This auto-oxidative inactivation seems to proceed via several catalytic pathways, including haem oxidation and the destruction of essential amino acids.…”

Synthesis of 1‐Naphthol by a Natural Peroxygenase Engineered by Directed Evolution

“…Moreover, it is known that some peroxidases have different inlets at the surface of the protein that serve for the one-electron oxidation of reducing substrates through a long-range electron transfer pathway towards the heme domain, as described here for W24F variants. [32] The R257K substitution may affect some of these enzyme circuits, possibly offering benefits in terms of improved thermostability through local rearrangements in secondary structures. Indeed, both the G241D and R257K mutations modified the local B factor profiles (Supplementary Figure S6).…”