| IED ID | IndEnz0018000543 |
| Enzyme Type ID | peroxidase000543 |
| Protein Name |
Flavohemoprotein Flavohemoglobin HMP Hemoglobin-like protein Nitric oxide dioxygenase NO oxygenase NOD EC 1.14.12.17 |
| Gene Name | hmp fsrB hmpA b2552 JW2536 |
| Organism | Escherichia coli (strain K12) |
| Taxonomic Lineage | cellular organisms Bacteria Proteobacteria Gammaproteobacteria Enterobacterales Enterobacteriaceae Escherichia Escherichia coli Escherichia coli (strain K12) |
| Enzyme Sequence | MLDAQTIATVKATIPLLVETGPKLTAHFYDRMFTHNPELKEIFNMSNQRNGDQREALFNAIAAYASNIENLPALLPAVEKIAQKHTSFQIKPEQYNIVGEHLLATLDEMFSPGQEVLDAWGKAYGVLANVFINREAEIYNENASKAGGWEGTRDFRIVAKTPRSALITSFELEPVDGGAVAEYRPGQYLGVWLKPEGFPHQEIRQYSLTRKPDGKGYRIAVKREEGGQVSNWLHNHANVGDVVKLVAPAGDFFMAVADDTPVTLISAGVGQTPMLAMLDTLAKAGHTAQVNWFHAAENGDVHAFADEVKELGQSLPRFTAHTWYRQPSEADRAKGQFDSEGLMDLSKLEGAFSDPTMQFYLCGPVGFMQFTAKQLVDLGVKQENIHYECFGPHKVL |
| Enzyme Length | 396 |
| Uniprot Accession Number | P24232 |
| Absorption | |
| Active Site | ACT_SITE 95; /note=Charge relay system; /evidence=ECO:0000269|PubMed:11092893; ACT_SITE 135; /note=Charge relay system; /evidence=ECO:0000269|PubMed:11092893 |
| Activity Regulation | |
| Binding Site | BINDING 188; /note=FAD |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=NADPH + 2 nitric oxide + 2 O2 = H(+) + NADP(+) + 2 nitrate; Xref=Rhea:RHEA:19465, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:16480, ChEBI:CHEBI:17632, ChEBI:CHEBI:57783, ChEBI:CHEBI:58349; EC=1.14.12.17; Evidence={ECO:0000269|PubMed:11751864}; CATALYTIC ACTIVITY: Reaction=NADH + 2 nitric oxide + 2 O2 = H(+) + NAD(+) + 2 nitrate; Xref=Rhea:RHEA:19469, ChEBI:CHEBI:15378, ChEBI:CHEBI:15379, ChEBI:CHEBI:16480, ChEBI:CHEBI:17632, ChEBI:CHEBI:57540, ChEBI:CHEBI:57945; EC=1.14.12.17; Evidence={ECO:0000269|PubMed:11751864}; |
| DNA Binding | |
| EC Number | 1.14.12.17 |
| Enzyme Function | FUNCTION: Is involved in NO detoxification in an aerobic process, termed nitric oxide dioxygenase (NOD) reaction that utilizes O(2) and NAD(P)H to convert NO to nitrate, which protects the bacterium from various noxious nitrogen compounds. Therefore, plays a central role in the inducible response to nitrosative stress.; FUNCTION: In the presence of oxygen and NADH, HMP has NADH oxidase activity, which leads to the generation of superoxide and H(2)O(2), both in vitro and in vivo, and it has been suggested that HMP might act as an amplifier of superoxide stress. Under anaerobic conditions, HMP also exhibits nitric oxide reductase and FAD reductase activities. However, all these reactions are much lower than NOD activity.; FUNCTION: Various electron acceptors are also reduced by HMP in vitro, including dihydropterine, ferrisiderophores, ferric citrate, cytochrome c, nitrite, S-nitrosoglutathione, and alkylhydroperoxides. However, it is unknown if these reactions are of any biological significance in vivo. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | NP_BIND 204..207; /note=FAD; NP_BIND 268..273; /note=NADP; /evidence=ECO:0000250; NP_BIND 389..392; /note=FAD |
| Features | Active site (2); Beta strand (14); Binding site (1); Chain (1); Domain (1); Helix (16); Metal binding (1); Mutagenesis (2); Nucleotide binding (3); Region (2); Site (3); Turn (1) |
| Keywords | 3D-structure;Cytoplasm;Detoxification;Direct protein sequencing;FAD;Flavoprotein;Heme;Iron;Metal-binding;NAD;NADP;Oxidoreductase;Oxygen transport;Reference proteome;Transport |
| Interact With | |
| Induction | INDUCTION: By nitric oxyde NO (under aerobic conditions), nitrite, nitrate (under anaerobic conditions), nitroso compounds, and paraquat. {ECO:0000269|PubMed:8808940, ECO:0000269|PubMed:9150210, ECO:0000269|PubMed:9767577}. |
| Subcellular Location | SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:7875569}. Note=Has also been found to localize into the periplasm, but spectral analysis revealed that biochemically active HMP is exclusively found in the cytoplasmic fraction. |
| Modified Residue | |
| Post Translational Modification | |
| Signal Peptide | |
| Structure 3D | X-ray crystallography (1) |
| Cross Reference PDB | 1GVH; |
| Mapped Pubmed ID | 16606699; 7821669; 8226691; |
| Motif | |
| Gene Encoded By | |
| Mass | 43,868 |
| Kinetics | BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=0.28 uM for NO {ECO:0000269|PubMed:10777548}; KM=90 uM for O(2) {ECO:0000269|PubMed:10777548}; KM=1.8 uM for NADH {ECO:0000269|PubMed:10777548}; KM=19.6 uM for NADPH {ECO:0000269|PubMed:10777548}; |
| Metal Binding | METAL 85; /note=Iron (heme b proximal ligand) |
| Rhea ID | RHEA:19465; RHEA:19469 |
| Cross Reference Brenda | 1.14.12.17; |