DEFINITION
A NADPH-oxidase is an enzyme that catalyzes the chemical reaction
NADPH + H+ + O2 --> NADP+ + H2O2
The substrates of this enzyme are NADPH, H+, and O2, whereas its 3 products are NADP+, and H2O2, the most widespread ROS
NADPH-oxidases family belongs to the family of oxidoreductases, specifically those acting on NADH or NADPH with oxygen as acceptor.
NOX (NADPH oxidase) enzymes are a family of heme containing trans membrane proteins. Their function is transport of electrons across the membrane from a cytosolic electron donor to an electron acceptor in the extra cellular or lumen space. NADPH serves as electron donor and oxygen as electron acceptor, with the overall result being the production of superoxide. The generation of ROS has been proposed to play a number of diverse roles, including cellular defense, cellular signaling, regulation of cell’ s death and growth, regulation of the redox potential and reduction of metal ions.
The most thoroughly studied of these is the leukocyte NADPH oxidase, which is found in professional phagocytes and B lymphocytes. the phagocyte NADPH oxidase was the first identified example of a system that generates ROS not as a byproduct, but rather as the primary function of the enzyme system. The discovery of other members of the NOX family of NADPH oxidases demonstrated that enzymes with the primary function of ROS generation are not limited to phagocytes
In parallel with the progress toward understanding the phagocyte NADPH oxidase, a series of observations suggest that enzyme systems similar to the phagocyte NADPH oxidase exist in many other cell types, including vascular smooth muscle.
American physiological society: vascular NADPH oxidase specific features 2003
THE GENE
CHEMICAL STRUCTURE AND IMAGES
When relevant for the function
- Primary structure
- Secondary structure
- Tertiary structure
- Quaternary structure
Protein Aminoacids Percentage
The Protein Aminoacids Percentage gives useful information on the local environment and the metabolic status of the cell (starvation, lack of essential AA, hypoxia)
Protein Aminoacids Percentage (Width 700 px)
SYNTHESIS AND TURNOVER
mRNA synthesis
protein synthesis
post-translational modifications
degradation
CELLULAR FUNCTIONS
cellular localization,
biological function
- Cell signaling and Ligand transport
- Structural proteins
REGULATION
DIAGNOSTIC USE
