Human Metabolome Database Version 3.5

Showing metabocard for Superoxide (HMDB02168)

Record Information
Version 3.5
Creation Date 2006-05-22 08:17:39 -0600
Update Date 2013-02-08 17:11:29 -0700
HMDB ID HMDB02168
Secondary Accession Numbers None
Metabolite Identification
Common Name Superoxide
Description Superoxide is the anionic form O2. It is important as the product of the one-electron reduction of dioxygen (oxygen gas), which occurs widely in nature. With one unpaired electron, the superoxide ion is a free radical. It is also paramagnetic. The biological toxicity of superoxide is due to its capacity to inactivate iron-sulfur cluster containing enzymes (which are critical in a wide variety of metabolic pathways), thereby liberating free iron in the cell, which can undergo fenton-chemistry and generate the highly reactive hydroxyl radical. In its HO2 form, superoxide can also initiate lipid peroxidation of polyunsaturated fatty acids. It also reacts with carbonyl compounds and halogenated carbons to create toxic peroxy radicals. As such, superoxide is a main cause of oxidative stress. Highly reactive compounds produced when oxygen is reduced by a single electron. In biological systems, they may be generated during the normal catalytic function of a number of enzymes and during the oxidation of hemoglobin to Methemoglobin. Because superoxide is toxic, nearly all organisms living in the presence of oxygen contain isoforms of the superoxide scavenging enzyme, superoxide dismutase, or SOD. SOD is an extremely efficient enzyme; it catalyzes the neutralization of superoxide nearly as fast as the two can diffuse together spontaneously in solution. Genetic inactivation ("knockout") of SOD produces deleterious phenotypes in organisms ranging from bacteria to mice. The latter species dies around 21 days after birth if the mitochondrial variant of SOD (Mn-SOD) is inactivated, and suffers from multiple pathologies, including reduced lifespan, liver cancer, muscle atrophy, cataracts and female infertility when the cytoplasmic (Cu, Zn -SOD) variant is inactivated. With one unpaired electron, the superoxide ion is a free radical and therefore paramagnetic. In living organisms, superoxide dismutase protects the cell from the deleterious effects of superoxides.
Structure Thumb
Download: MOL | SDF | PDB | SMILES | InChI
Display: 2D Structure | 3D Structure
Synonyms
  1. Dioxidanidyl
  2. Dioxide(1-)
  3. Hyperoxid
  4. Superoxide
  5. Superoxide anion
  6. Superoxide radical
  7. Superoxide radical anion
Chemical Formula O2
Average Molecular Weight 31.9988
Monoisotopic Molecular Weight 31.989829244
IUPAC Name oxidanidyloxidanyl
Traditional IUPAC Name superoxide
CAS Registry Number 11062-77-4
SMILES [O][O-]
InChI Identifier InChI=1S/HO2/c1-2/h1H/p-1
InChI Key OUUQCZGPVNCOIJ-UHFFFAOYSA-M
Chemical Taxonomy
Kingdom Inorganic Compounds
Super Class Homogeneous Non-metal Compounds
Class Non-metal Oxoanionic Compounds
Sub Class Non-metal Superoxides
Other Descriptors
  • diatomic oxygen(ChEBI)
  • inorganic radical anion(ChEBI)
  • reactive oxygen species(ChEBI)
Substituents
  • N/A
Direct Parent Non-metal Superoxides
Ontology
Status Expected and Not Quantified
Origin
  • Endogenous
Biofunction
  • Osmolyte, enzyme cofactor, signalling
Application Not Available
Cellular locations
  • Cytoplasm
  • Extracellular
  • Mitochondria
  • Nucleus
  • Peroxisome
Physical Properties
State Solid
Experimental Properties
Property Value Reference
Melting Point Not Available Not Available
Boiling Point Not Available Not Available
Water Solubility Not Available Not Available
LogP Not Available Not Available
Predicted Properties
Property Value Source
Water Solubility ALOGPS
LogP -0.36 ChemAxon
pKa (strongest acidic) 5.8 ChemAxon
pKa (strongest basic) -6.8 ChemAxon
Hydrogen Acceptor Count 2 ChemAxon
Hydrogen Donor Count 0 ChemAxon
Polar Surface Area 23.06 A2 ChemAxon
Rotatable Bond Count 0 ChemAxon
Refractivity 2.89 ChemAxon
Polarizability 1.67 ChemAxon
Formal Charge -1 ChemAxon
Physiological Charge -1 ChemAxon
Spectra
Not Available
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Mitochondria
  • Nucleus
  • Peroxisome
Biofluid Locations Not Available
Tissue Location Not Available
Pathways
Name SMPDB Link KEGG Link
Degradation of Superoxides SMP00468 Not Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease References None
Associated OMIM IDs None
DrugBank ID Not Available
DrugBank Metabolite ID Not Available
Phenol Explorer Compound ID Not Available
Phenol Explorer Metabolite ID Not Available
FoodDB ID FDB022880
KNApSAcK ID Not Available
Chemspider ID 4514331 Link_out
KEGG Compound ID C00704 Link_out
BioCyc ID Not Available
BiGG ID 35743 Link_out
Wikipedia Link Superoxide Link_out
NuGOwiki Link HMDB02168 Link_out
Metagene Link HMDB02168 Link_out
METLIN ID Not Available
PubChem Compound 5359597 Link_out
PDB ID Not Available
ChEBI ID 18421 Link_out
References
Synthesis Reference Not Available
Material Safety Data Sheet (MSDS) Not Available
General References Not Available

Enzymes
Name: Catalase
Reactions:
3-Hydroxyanthranilic acid + Oxygen unknown Cinnavalininate + Superoxide + Hydrogen peroxide + Hydrogen Ion details
Gene Name: CAT
Uniprot ID: P04040 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
Name: Superoxide dismutase [Mn], mitochondrial
Reactions:
Superoxide + Hydrogen Ion unknown Oxygen + Hydrogen peroxide details
Gene Name: SOD2
Uniprot ID: P04179 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
Name: Superoxide dismutase [Cu-Zn]
Reactions:
Superoxide + Hydrogen Ion unknown Oxygen + Hydrogen peroxide details
Gene Name: SOD1
Uniprot ID: P00441 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA
Name: Extracellular superoxide dismutase [Cu-Zn]
Reactions:
Superoxide + Hydrogen Ion unknown Oxygen + Hydrogen peroxide details
Gene Name: SOD3
Uniprot ID: P08294 Link_out
Protein Sequence: FASTA
Gene Sequence: FASTA