Cytochrome b-245 heavy chain (NOX2) (NOX2)

Cytochrome b-245 heavy chain, commonly referred to as gp91-phox or NOX2, is the primary catalytic subunit of the phagocyte NADPH oxidase complex (UniProt P04839). It is a transmembrane protein that facilitates the transfer of electrons from NADPH to molecular oxygen, resulting in the production of superoxide anions (NCBI Gene: 1536). This respiratory burst is a critical component of the innate immune system, enabling phagocytes such as neutrophils and macrophages to destroy invading pathogens (StatPearls: Chronic Granulomatous Disease). While essential for host defense, dysregulated or excessive NOX2 activity is a major source of oxidative stress, contributing to the pathogenesis of inflammatory diseases, neurodegeneration, and cardiovascular disorders (Bedard & Krause, 2007). Mutations in the CYBB gene, which encodes this protein, result in X-linked Chronic Granulomatous Disease (CGD), a condition marked by life-threatening infections and granuloma formation (StatPearls). Consequently, NOX2 is a high-priority target for the development of antioxidants and anti-inflammatory therapies aimed at modulating reactive oxygen species production. Pharmacological inhibition of NOX2 is being explored to treat conditions like stroke and myocardial infarction where oxidative damage is prevalent. However, therapeutic strategies must balance the reduction of harmful ROS with the preservation of essential immune functions.

Other names

gp91-phoxCYBBCytochrome b(558) subunit betaNADPH oxidase 2CGD91-phoxHeme-binding membrane glycoprotein gp91phox

Inhibition of the catalytic activity of the NOX2 complex to prevent the generation of superoxide anions from molecular oxygen (UniProt P04839).