modENCODE |  Help |  blog

Protein Domain : IPR012144

Name  Nitric-oxide synthase, eukaryote Short Name  NOS_euk
Type  Family Description  Nitric oxide synthase () (NOS) enzymes produce nitric oxide (NO) by catalyzing a five-electron oxidation of a guanidino nitrogen of L-arginine (L-Arg). Oxidation of L-Arg to L-citrulline occurs via two successive monooxygenation reactions producing N(omega)-hydroxy-L-arginine as an intermediate. 2 mol of O(2) and 1.5 mol of NADPH are consumed per mole of NO formed [].Arginine-derived NO synthesis has been identified in mammals, fish, birds, invertebrates, plants, and bacteria []. Best studied are mammals, where three distinct genes encode NOS isozymes: neuronal (nNOS or NOS-1), cytokine-inducible (iNOS or NOS-2) and endothelial (eNOS or NOS-3) []. iNOS and nNOS are soluble and found predominantly in the cytosol, while eNOS is membrane associated. The enzymes exist as homodimers, each monomer consisting of two major domains: an N-terminal oxygenase domain, which belongs to the class of haem-thiolate proteins, and a C-terminal reductase domain, which is homologous to NADPH:P450 reductase (). The interdomain linker between the oxygenase and reductase domains contains a calmodulin (CaM)-binding sequence. NOSs are the only enzymes known to simultaneously require five bound cofactors animal NOS isozymes are catalytically self-sufficient. The electron flow in the NO synthase reaction is: NADPH -->FAD -->FMN -->haem -->O(2).eNOS localisation to endothelial membranes is mediated by cotranslational N-terminal myristoylation and post-translational palmitoylation []. The subcellular localisation of nNOS in skeletal muscle is mediated by anchoring of nNOS to dystrophin. nNOS contains an additional N-terminal domain, the PDZ domain [].This entry represents all forms of NOS from eukaryotes. For further information see [, , , ].

Publication Counts Displayer

0 Child Features

2 Contains

DB identifier Name Short Name Type
IPR003097 FAD-binding, type 1 FAD-binding_1 Domain
IPR004030 Nitric oxide synthase, oxygenase domain NO_synthase_oxygenase_dom Domain

1 Cross References

Identifier
Source . Name

Subject . Primary Identifier
PIRSF000333 PIRSF IPR012144

3 Data Sets

Name URL
TrEMBL data set http://www.ebi.ac.uk/trembl/
InterPro data set  
InterPro GO Annotation data set  

0 Found In

8 GO Annotation


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
Nitric-oxide synthase, eukaryote   GO:0004517 nitric-oxide synthase activity
Nitric-oxide synthase, eukaryote   GO:0005506 iron ion binding
Nitric-oxide synthase, eukaryote   GO:0005516 calmodulin binding
Nitric-oxide synthase, eukaryote   GO:0010181 FMN binding
Nitric-oxide synthase, eukaryote   GO:0020037 heme binding
Nitric-oxide synthase, eukaryote   GO:0050660 flavin adenine dinucleotide binding
Nitric-oxide synthase, eukaryote   GO:0050661 NADP binding
Nitric-oxide synthase, eukaryote   GO:0006809 nitric oxide biosynthetic process

8 Ontology Annotations


Subject . Secondary Identifier

Subject . Name

Subject . Symbol

Ontology Term . Identifier

Ontology Term . Name
Nitric-oxide synthase, eukaryote   GO:0004517 nitric-oxide synthase activity
Nitric-oxide synthase, eukaryote   GO:0005506 iron ion binding
Nitric-oxide synthase, eukaryote   GO:0005516 calmodulin binding
Nitric-oxide synthase, eukaryote   GO:0010181 FMN binding
Nitric-oxide synthase, eukaryote   GO:0020037 heme binding
Nitric-oxide synthase, eukaryote   GO:0050660 flavin adenine dinucleotide binding
Nitric-oxide synthase, eukaryote   GO:0050661 NADP binding
Nitric-oxide synthase, eukaryote   GO:0006809 nitric oxide biosynthetic process

0 Parent Features

11 Proteins

DB identifier Primary Accession
Organism . Name
FBpp0079777 Q27571 Drosophila melanogaster
FBpp0287477 Q29KP6 Drosophila pseudoobscura
FBpp0167029 B4KKM7 Drosophila mojavensis
FBpp0232056 B4LS74 Drosophila virilis
FBpp0258305 B4P121 Drosophila yakuba
NOS_DROME-6 Q27571-6 Drosophila melanogaster
NOS_DROME-2 Q27571-2 Drosophila melanogaster
NOS_DROME-3 Q27571-3 Drosophila melanogaster
NOS_DROME-4 Q27571-4 Drosophila melanogaster
NOS_DROME-7 Q27571-7 Drosophila melanogaster
NOS_DROME-5 Q27571-5 Drosophila melanogaster