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Record Information
Creation Date2014-08-29 06:51:32 UTC
Update Date2018-03-21 17:46:24 UTC
Accession NumberT3D4466
Common NameSulfite
ClassSmall Molecule
DescriptionEndogenous sulfite is generated as a consequence of the body's normal processing of sulfur-containing amino acids. Sulfites occur as a consequence of fermentation and also occur naturally in a number of foods and beverages. As food additives, sulfiting agents were first used in 1664 and have been approved in the United States since the 1800s. Sulfite is an allergen, a neurotoxin, and a metabotoxin. An allergen is a compound that causes allergic reactions such as wheezing, rash, or rhinitis. A neurotoxin is a substance that causes damage to nerves or brain tissues. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. As an allergen, sulfite is known to induce asthmatic reactions. Sulfite sensitivity occurs most often in asthmatic adults (predominantly women), but it is also occasionally reported in preschool children. Adverse reactions to sulfites in nonasthmatics are extremely rare. Asthmatics who are steroid-dependent or who have a higher degree of airway hyperreactivity may be at greater risk of experiencing a reaction to sulfite-containing foods. Sulfite sensitivity reactions vary widely, ranging from no reaction to severe. The majority of reactions are mild. These manifestations may include dermatologic, respiratory, or gastrointestinal signs and symptoms. The precise mechanisms of the sensitivity responses have not been completely elucidated: inhalation of sulfur dioxide (SO2) generated in the stomach following ingestion of sulfite-containing foods or beverages, a deficiency in a mitochondrial enzyme, and an IgE-mediated immune response have all been implicated. Exogenously supplied sulfite is detoxified by the enzyme sulfite oxidase. Sulfite oxidase (EC is 1 of 3 enzymes in humans that require molybdenum as a cofactor. Under certain circumstances, chronically high levels of sulfite can lead to serious neurotoxicity. Sulfite oxidase deficiency (also called molybdenum cofactor deficiency) is a rare autosomal inherited disease that is typified by high concentrations of sulfite in the blood and urine. It is characterized by severe neurological symptoms such as untreatable seizures, attenuated growth of the brain, and mental retardation. It results from defects in the enzyme sulfite oxidase, which is responsible for the oxidation of sulfite to sulfate. This sulfite to sulfate reaction is the final step in the degradation of sulfur-containing metabolites (including the amino acids cysteine and methionine). The term "isolated sulfite oxidase deficiency" is used to define the deficiency caused by mutations in the sulfite oxidase gene. This differentiates it from another version of sulfite oxidase deficiency that is due to defects in the molybdenum cofactor biosynthetic pathway (with mutations in the MOCS1 or MOCS2 genes). Isolated sulfite oxidase deficiency is a rare but devastating neurologic disease that usually presents in early infancy with seizures and alterations in muscle tone (PMID: 16234925, 16140720, 8586770). Sulfite oxidase deficiency (as caused by MOCS1 or MOCS2) may be treated with cPMP, a precursor of the molybdenum cofactor (PMID: 20385644). The mechanism behind sulfite neurotoxicity appears to be related to its ability to bind and inhibit glutamate dehydrogenase (GDH). Inhibition of GDH leads to a decrease in alpha-ketoglutarate and a diminished flux through the tricarboxylic acid cycle. This is accompanied by a decrease in NADH through the mitochondrial electron transport chain, which leads to a decrease in mitochondrial membrane potential and in ATP synthesis. Since glutamate is a major metabolite in the brain, inhibition of GDH by sulfite appears to contribute to neural damage characteristic of sulfite oxidase deficiency in human infants (PMID: 15273247).
Compound Type
  • Animal Toxin
  • Food Additive
  • Food Toxin
  • Inorganic Compound
  • Metabolite
  • Natural Compound
  • Non-Metal
Chemical Structure
Sulfite dianion
Sulfite ion
Sulfite ions
Sulfur trioxide
Sulfuric anhydride
Chemical FormulaO3S
Average Molecular Mass80.064 g/mol
Monoisotopic Mass79.958 g/mol
CAS Registry Number14265-45-3
IUPAC Namesulfurous acid
Traditional Namesulfurous acid
InChI IdentifierInChI=1S/H2O3S/c1-4(2)3/h(H2,1,2,3)/p-2
Chemical Taxonomy
Description belongs to the class of inorganic compounds known as non-metal sulfites. These are inorganic non-metallic compounds containing a sulfite as its largest oxoanion.
KingdomInorganic compounds
Super ClassHomogeneous non-metal compounds
ClassNon-metal oxoanionic compounds
Sub ClassNon-metal sulfites
Direct ParentNon-metal sulfites
Alternative Parents
  • Non-metal sulfite
  • Inorganic oxide
Molecular FrameworkNot Available
External Descriptors
Biological Properties
StatusDetected and Not Quantified
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Mitochondria
Biofluid LocationsNot Available
Tissue Locations
  • Brain
  • Neutrophil
Sulfate/Sulfite MetabolismSMP00041 map00920
Sulfite oxidase deficiencySMP00532 Not Available
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
AppearanceWhite powder.
Experimental Properties
Melting PointNot Available
Boiling PointNot Available
Solubility558.5 mg/mL
LogPNot Available
Predicted Properties
pKa (Strongest Acidic)1.7ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area57.53 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity12.33 m³·mol⁻¹ChemAxon
Polarizability5.76 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-001i-9000000000-6e01fa26fbebd72ad6ac2017-09-01View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot Available2021-10-12View Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-0ue9-9000000000-f7ae469c0c0eb80e5bb92018-05-15View Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-001i-9300000000-8bbaba610a5e9ef617fe2018-05-15View Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-0udi-9300000000-460847a9238bf81b4b9c2018-05-15View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-9000000000-0d5af2beca96b50eac8a2015-09-14View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-9000000000-42884a642ace9e213e652015-09-14View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-01q9-9000000000-5357c61e80aaefe2133c2015-09-14View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-9000000000-a7737b78e8d12bda45592015-09-15View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-9000000000-1920e0308a2b8b74a3f42015-09-15View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-001i-9000000000-1920e0308a2b8b74a3f42015-09-15View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-9000000000-a6fb8cd4d3dc149be3092021-09-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-9000000000-a6fb8cd4d3dc149be3092021-09-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-001i-9000000000-a6fb8cd4d3dc149be3092021-09-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-9000000000-95d8eaf2b829c52ced6c2021-09-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-03di-9000000000-2c4a3db8921d94d7f5262021-09-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-03di-9000000000-2c4a3db8921d94d7f5262021-09-24View Spectrum
Toxicity Profile
Route of ExposureNot Available
Mechanism of ToxicityNot Available
MetabolismNot Available
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesAs food additives, sulfiting agents were first used in 1664 and approved in the United States as long ago as the 1800s.
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
PubChem Compound ID1099
ChEMBL IDNot Available
ChemSpider ID1068
UniProt IDNot Available
ChEBI ID17359
BioCyc IDSO3
CTD IDNot Available
Stitch IDNot Available
ACToR IDNot Available
Wikipedia LinkSulfite
Synthesis ReferenceDorain, P. B.; Von Raben, K. U.; Chang, R. K.; Laube, B. L. Catalytic formation of sulfite and sulfate ions from sulfur dioxide on silver observed by surface-enhanced Raman scattering. Chemical Physics Letters (1981), 84(2), 405-9.
General References
  1. Karakas E, Kisker C: Structural analysis of missense mutations causing isolated sulfite oxidase deficiency. Dalton Trans. 2005 Nov 7;(21):3459-63. Epub 2005 Sep 26. [16234925 ]
  2. Tan WH, Eichler FS, Hoda S, Lee MS, Baris H, Hanley CA, Grant PE, Krishnamoorthy KS, Shih VE: Isolated sulfite oxidase deficiency: a case report with a novel mutation and review of the literature. Pediatrics. 2005 Sep;116(3):757-66. [16140720 ]
  3. Lester MR: Sulfite sensitivity: significance in human health. J Am Coll Nutr. 1995 Jun;14(3):229-32. [8586770 ]
  4. Graf WD, Oleinik OE, Jack RM, Weiss AH, Johnson JL: Ahomocysteinemia in molybdenum cofactor deficiency. Neurology. 1998 Sep;51(3):860-2. [9748040 ]
  5. Jeppesen C: Media for Aeromonas spp., Plesiomonas shigelloides and Pseudomonas spp. from food and environment. Int J Food Microbiol. 1995 Jun;26(1):25-41. [7662518 ]
  6. Mitsuhashi H, Nojima Y, Tanaka T, Ueki K, Maezawa A, Yano S, Naruse T: Sulfite is released by human neutrophils in response to stimulation with lipopolysaccharide. J Leukoc Biol. 1998 Nov;64(5):595-9. [9823763 ]
  7. von Graevenitz A, Bucher C: Evaluation of differential and selective media for isolation of Aeromonas and Plesiomonas spp. from human feces. J Clin Microbiol. 1983 Jan;17(1):16-21. [6826700 ]
  8. Tsariuk LA, Rybachuk VN, Shevchenko LI, Tolstykh VM: [Determination of fibrinogen concentration in blood plasma by the sulfite precipitation method]. Vopr Med Khim. 1979 Jan-Feb;25(1):97-101. [425377 ]
  9. Shea M, Howell S: High-performance liquid chromatographic measurement of exogenous thiosulfate in urine and plasma. Anal Biochem. 1984 Aug 1;140(2):589-94. [6486442 ]
  10. Bor-Kucukatay M, Kucukatay V, Agar A, Baskurt OK: Effect of sulfite on red blood cell deformability ex vivo and in normal and sulfite oxidase-deficient rats in vivo. Arch Toxicol. 2005 Sep;79(9):542-6. Epub 2005 Apr 13. [15827731 ]
  11. Gubash SM, Ingham L: Comparison of a new, bismuth-iron-sulfite-cycloserine agar for isolation of Clostridium perfringens with the tryptose-sulfite-cycloserine and blood agars. Zentralbl Bakteriol. 1997 Feb;285(3):397-402. [9084113 ]
  12. Kim E, Driscoll CF, Minah GE: The effect of a denture adhesive on the colonization of Candida species in vivo. J Prosthodont. 2003 Sep;12(3):187-91. [14508740 ]
  13. Willis CL, Cummings JH, Neale G, Gibson GR: Nutritional aspects of dissimilatory sulfate reduction in the human large intestine. Curr Microbiol. 1997 Nov;35(5):294-8. [9462959 ]
  14. Sardesai VM: Molybdenum: an essential trace element. Nutr Clin Pract. 1993 Dec;8(6):277-81. [8302261 ]
  15. Togawa T, Ogawa M, Nawata M, Ogasawara Y, Kawanabe K, Tanabe S: High performance liquid chromatographic determination of bound sulfide and sulfite and thiosulfate at their low levels in human serum by pre-column fluorescence derivatization with monobromobimane. Chem Pharm Bull (Tokyo). 1992 Nov;40(11):3000-4. [1477915 ]
  16. Pearson SJ, Czudek C, Mercer K, Reynolds GP: Electrochemical detection of human brain transmitter amino acids by high-performance liquid chromatography of stable o-phthalaldehyde-sulphite derivatives. J Neural Transm Gen Sect. 1991;86(2):151-7. [1683240 ]
  17. Mishra A, Dayal N, Beck-Speier I: Effect of sulphite on the oxidative metabolism of human neutrophils: studies with lucigenin- and luminol-dependent chemiluminescence. J Biolumin Chemilumin. 1995 Jan-Feb;10(1):9-19. [7762419 ]
  18. Beck-Speier I, Lenz AG, Godleski JJ: Responses of human neutrophils to sulfite. J Toxicol Environ Health. 1994 Mar;41(3):285-97. [8126751 ]
  19. Beck-Speier I, Liese JG, Belohradsky BH, Godleski JJ: Sulfite stimulates NADPH oxidase of human neutrophils to produce active oxygen radicals via protein kinase C and Ca2+/calmodulin pathways. Free Radic Biol Med. 1993 Jun;14(6):661-8. [8392022 ]
  20. Zhang X, Vincent AS, Halliwell B, Wong KP: A mechanism of sulfite neurotoxicity: direct inhibition of glutamate dehydrogenase. J Biol Chem. 2004 Oct 8;279(41):43035-45. Epub 2004 Jul 23. [15273247 ]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available