The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle

Stable Identifier
R-HSA-1497784
Type
Reaction [transition]
Species
Homo sapiens
Compartment
cytosol, plasma membrane
ReviewStatus
5/5
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The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle
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The cofactor tetrahydrobiopterin (BH4) ensures endothelial nitric oxide synthase (eNOS) couples electron transfer to L-arginine oxidation (Berka et al. 2004). During catalysis, electrons derived from NADPH transfer to the flavins FAD and FMN in the reductase domain of eNOS and then on to the ferric heme in the oxygenase domain of eNOS. BH4 can donate an electron to intermediates in this electron transfer and is oxidised in the process, forming the BH3 radical. This radical can be reduced back to BH4 by iron, completing the cycle and forming ferrous iron again. Heme reduction enables O2 binding and L-arginine oxidation to occur within the oxygenase domain (Stuehr et al. 2009).
Literature References
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Output
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as an event of
Catalyst Activity

tetrahydrobiopterin binding activity of p-S1177-eNOS:CaM:HSP90:p-AKT1 [plasma membrane]

Physical Entity
p-S1177-eNOS:CaM:HSP90:p-AKT1 [plasma membrane] (Homo sapiens)
Activity
tetrahydrobiopterin binding (GO:0034617)
Orthologous Events
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Bos taurus)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Caenorhabditis elegans)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Dictyostelium discoideum)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Drosophila melanogaster)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Mus musculus)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Rattus norvegicus)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Saccharomyces cerevisiae)
The cofactor BH4 is required for electron transfer in the eNOS catalytic cycle (Schizosaccharomyces pombe)
Authored
Jassal, B  (2011-08-17)
Reviewed
D'Eustachio, P  (2011-08-23)
Hill, DP  (2024-08-02)
Created
Jassal, B  (2011-08-17)
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