NQO1 Human
Description
The NQO1 is purified by proprietary chromatographic techniques.
Product Specs
Product Science Overview
NQO1 is a cytoplasmic, homodimeric protein that binds one FAD (flavin adenine dinucleotide) molecule per monomer . It functions as a two-electron reductase, reducing quinones to hydroquinones and preventing the formation of semiquinone radicals and reactive oxygen species (ROS) . This reduction process is essential for detoxifying quinones and protecting cells from oxidative damage .
NQO1 uses NADH or NADPH as reducing cofactors to catalyze the reduction of quinones . The enzyme’s activity is characterized by its inhibition by dicoumarol . By facilitating the two-electron reduction of quinones, NQO1 indirectly prevents the one-electron reduction that leads to the formation of harmful semiquinone free radicals .
NQO1 is involved in various biological processes, including:
- Detoxification: NQO1 removes quinones from biological systems through a detoxification reaction, thereby preventing the formation of damaging semiquinone and oxygen free radical species .
- Antioxidant Defense: The enzyme acts as a protective antioxidant agent, regulating oxidative stress and protecting cells from DNA damage .
- Vitamin K Metabolism: NQO1 is involved in the reduction of vitamin K1, K2, and K3 into their hydroquinone forms, which are essential for the gamma-carboxylation of glutamate residues in prothrombin synthesis .
NQO1 has been found to be overexpressed in various tumor cells, including those of the breast, lung, cervix, pancreas, and colon . This overexpression is associated with the enzyme’s role in protecting cells from oxidative stress and its involvement in the stabilization of the tumor suppressor protein p53 . Individuals with decreased NQO1 expression or activity may have reduced p53 stability, leading to resistance to certain chemotherapeutic drugs .
