Uncoupled eNOS favours the formation of superoxide

Stable Identifier
R-HSA-1497810
Type
Reaction [transition]
Species
Homo sapiens
Compartment
cytosol, plasma membrane
Synonyms
NADPH + 2 O2 => H(+) + NADP(+) + 2 superoxide
ReviewStatus
5/5
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Uncoupled eNOS favours the formation of superoxide
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BH2 may compete with BH4 to bind eNOS, uncoupling eNOS leading to the formation of superoxide rather than nitric oxide. BH2, the oxidised form of BH4, cannot contribute electrons to heme in the reductase domain of eNOS, thereby uncoupling it from arginine oxidation and producing superoxide from oxygen instead (Vasquez-Vivar et al. 2002).
Literature References
PubMed ID Title Journal Year
11879202 The ratio between tetrahydrobiopterin and oxidized tetrahydrobiopterin analogues controls superoxide release from endothelial nitric oxide synthase: an EPR spin trapping study

Kalyanaraman, B, Joseph, J, Whitsett, J, Vásquez-Vivar, J, Martasek, P

Biochem J 2002
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Catalyst Activity

superoxide-generating NAD(P)H oxidase activity of p-S1177-eNOS:CaM:HSP90:p-AKT1:BH2 [plasma membrane]

Physical Entity
p-S1177-eNOS:CaM:HSP90:p-AKT1:BH2 [plasma membrane] (Homo sapiens)
Activity
superoxide-generating NAD(P)H oxidase activity (GO:0016175)
Orthologous Events
Uncoupled eNOS favours the formation of superoxide (Bos taurus)
Uncoupled eNOS favours the formation of superoxide (Caenorhabditis elegans)
Uncoupled eNOS favours the formation of superoxide (Dictyostelium discoideum)
Uncoupled eNOS favours the formation of superoxide (Drosophila melanogaster)
Uncoupled eNOS favours the formation of superoxide (Gallus gallus)
Uncoupled eNOS favours the formation of superoxide (Mus musculus)
Uncoupled eNOS favours the formation of superoxide (Plasmodium falciparum)
Uncoupled eNOS favours the formation of superoxide (Rattus norvegicus)
Uncoupled eNOS favours the formation of superoxide (Saccharomyces cerevisiae)
Uncoupled eNOS favours the formation of superoxide (Schizosaccharomyces pombe)
Uncoupled eNOS favours the formation of superoxide (Sus scrofa)
Cross References
RHEA
Rhea
Authored
Jassal, B  (2011-08-17)
Reviewed
D'Eustachio, P  (2011-08-23)
Created
Jassal, B  (2011-08-17)
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