thiol oxidase activity

Definition

Target type: molecularfunction

Catalysis of the reaction: 2 R'C(R)SH + O2 = R'C(R)S-S(R)CR' + 2 H2O2. [RHEA:17357]

Thiol oxidase activity is a crucial enzymatic process involved in the oxidation of thiol (-SH) groups, often found in cysteine residues within proteins. This oxidation reaction converts the thiol group to a disulfide bond (-S-S-), forming a bridge between two cysteine residues. This disulfide bond formation plays a significant role in protein folding, stability, and regulation.

Thiol oxidases are typically involved in various cellular processes, including:

* **Protein folding:** Disulfide bonds formed by thiol oxidases help stabilize protein structures, promoting proper folding and preventing misfolding.
* **Redox regulation:** The oxidation of thiol groups can alter protein activity, often acting as a regulatory mechanism in signal transduction pathways.
* **Cellular detoxification:** Some thiol oxidases help detoxify reactive oxygen species (ROS) by oxidizing thiol groups in proteins that have been damaged by ROS.
* **Oxidative stress response:** Thiol oxidases can participate in the cellular response to oxidative stress by mediating the formation of disulfide bonds in proteins, influencing the overall cellular redox state.

The specific mechanism of thiol oxidase activity can vary depending on the enzyme, but generally involves the transfer of electrons from the thiol group to an electron acceptor, often an oxygen molecule. This process results in the formation of the disulfide bond and the reduction of the electron acceptor.

In summary, thiol oxidase activity is a vital enzymatic function responsible for the oxidation of thiol groups, contributing to protein folding, regulation, detoxification, and cellular responses to oxidative stress. '
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Proteins (1)

Compounds (2)