L-Cysteine
Relevant Data
Food Additives Approved in the United States:
Food Additives Approved by WHO:
General Information
| Chemical name | L-Cysteine |
| CAS number | 52-90-4 |
| COE number | 10464 |
| JECFA number | 1419 |
| Flavouring type | substances |
| FL No. | 17.033 |
| Mixture | No |
| Purity of the named substance at least 95% unless otherwise specified | |
| Reference body | EFSA |
From webgate.ec.europa.eu
Computed Descriptors
Download SDF| 2D Structure | |
| CID | 5862 |
| IUPAC Name | (2R)-2-amino-3-sulfanylpropanoic acid |
| InChI | InChI=1S/C3H7NO2S/c4-2(1-7)3(5)6/h2,7H,1,4H2,(H,5,6)/t2-/m0/s1 |
| InChI Key | XUJNEKJLAYXESH-REOHCLBHSA-N |
| Canonical SMILES | C(C(C(=O)O)N)S |
| Molecular Formula | C3H7NO2S |
| Wikipedia | cysteine |
From Pubchem
Computed Properties
| Property Name | Property Value |
|---|---|
| Molecular Weight | 121.154 |
| Hydrogen Bond Donor Count | 3 |
| Hydrogen Bond Acceptor Count | 4 |
| Rotatable Bond Count | 2 |
| Complexity | 75.3 |
| CACTVS Substructure Key Fingerprint | A A A D c Y B C M A B A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A H g Q Q C A A A C C j F w A S A C A B A A g Q I A A C Q C A A A A A A A A A A A A I G A A A A C A A A A A A A A Q A A A E A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A = = |
| Topological Polar Surface Area | 64.3 |
| Monoisotopic Mass | 121.02 |
| Exact Mass | 121.02 |
| Compound Is Canonicalized | True |
| Formal Charge | 0 |
| Heavy Atom Count | 7 |
| Defined Atom Stereocenter Count | 1 |
| Undefined Atom Stereocenter Count | 0 |
| Defined Bond Stereocenter Count | 0 |
| Undefined Bond Stereocenter Count | 0 |
| Isotope Atom Count | 0 |
| Covalently-Bonded Unit Count | 1 |
From Pubchem
Food Additives Biosynthesis/Degradation
ADMET Predicted Profile --- Classification
| Model | Result | Probability |
|---|---|---|
| Absorption | ||
| Blood-Brain Barrier | BBB+ | 0.5918 |
| Human Intestinal Absorption | HIA+ | 0.9698 |
| Caco-2 Permeability | Caco2- | 0.7210 |
| P-glycoprotein Substrate | Non-substrate | 0.8141 |
| P-glycoprotein Inhibitor | Non-inhibitor | 0.9840 |
| Non-inhibitor | 0.9903 | |
| Renal Organic Cation Transporter | Non-inhibitor | 0.9462 |
| Distribution | ||
| Subcellular localization | Lysosome | 0.7697 |
| Metabolism | ||
| CYP450 2C9 Substrate | Non-substrate | 0.8473 |
| CYP450 2D6 Substrate | Non-substrate | 0.8141 |
| CYP450 3A4 Substrate | Non-substrate | 0.8245 |
| CYP450 1A2 Inhibitor | Non-inhibitor | 0.9400 |
| CYP450 2C9 Inhibitor | Non-inhibitor | 0.9584 |
| CYP450 2D6 Inhibitor | Non-inhibitor | 0.9665 |
| CYP450 2C19 Inhibitor | Non-inhibitor | 0.9634 |
| CYP450 3A4 Inhibitor | Non-inhibitor | 0.9602 |
| CYP Inhibitory Promiscuity | Low CYP Inhibitory Promiscuity | 0.9888 |
| Excretion | ||
| Toxicity | ||
| Human Ether-a-go-go-Related Gene Inhibition | Weak inhibitor | 0.9891 |
| Non-inhibitor | 0.9684 | |
| AMES Toxicity | AMES toxic | 0.9107 |
| Carcinogens | Non-carcinogens | 0.7998 |
| Fish Toxicity | Low FHMT | 0.7709 |
| Tetrahymena Pyriformis Toxicity | Low TPT | 0.9922 |
| Honey Bee Toxicity | Low HBT | 0.5092 |
| Biodegradation | Ready biodegradable | 0.7577 |
| Acute Oral Toxicity | III | 0.8014 |
| Carcinogenicity (Three-class) | Non-required | 0.7251 |
From admetSAR
ADMET Predicted Profile --- Regression
| Model | Value | Unit |
|---|---|---|
| Absorption | ||
| Aqueous solubility | 0.1127 | LogS |
| Caco-2 Permeability | 0.2031 | LogPapp, cm/s |
| Distribution | ||
| Metabolism | ||
| Excretion | ||
| Toxicity | ||
| Rat Acute Toxicity | 1.7757 | LD50, mol/kg |
| Fish Toxicity | 3.0761 | pLC50, mg/L |
| Tetrahymena Pyriformis Toxicity | -0.8730 | pIGC50, ug/L |
From admetSAR
Toxicity Profile
| Route of Exposure | Endogenous, Ingestion, Dermal (contact) |
|---|---|
| Mechanism of Toxicity | Uremic toxins such as cysteine are actively transported into the kidneys via organic ion transporters (especially OAT3). Increased levels of uremic toxins can stimulate the production of reactive oxygen species. This seems to be mediated by the direct binding or inhibition by uremic toxins of the enzyme NADPH oxidase (especially NOX4 which is abundant in the kidneys and heart) . Reactive oxygen species can induce several different DNA methyltransferases (DNMTs) which are involved in the silencing of a protein known as KLOTHO. KLOTHO has been identified as having important roles in anti-aging, mineral metabolism, and vitamin D metabolism. A number of studies have indicated that KLOTHO mRNA and protein levels are reduced during acute or chronic kidney diseases in response to high local levels of reactive oxygen species . Although classified as a non-essential amino acid cysteine may be essential for infants, the elderly, and individuals with certain metabolic disease or who suffer from malabsorption syndromes. Cysteine can usually be synthesized by the human body under normal physiological conditions if a sufficient quantity of methionine is available. Due to the ability of thiols to undergo redox reactions, cysteine has antioxidant properties. Cysteine's antioxidant properties are typically expressed in the tripeptide glutathione, which occurs in humans as well as other organisms. The systemic availability of oral glutathione (GSH) is negligible; so it must be biosynthesized from its constituent amino acids, cysteine, glycine, and glutamic acid. Glutamic acid and glycine are readily available in the diets of most industrialized countries, but the availability of cysteine can be the limiting substrate. Cysteine is also an important source of sulfide in human metabolism. The sulfide in iron-sulfur clusters and in nitrogenase is extracted from cysteine, which is converted to alanine in the process. In a 1994 report released by five top cigarette companies, cysteine is one of the 599 additives to cigarettes. Its use or purpose, however, is unknown, like most cigarette additives. Its inclusion in cigarettes could offer two benefits: Acting as an expectorant, since smoking increases mucus production in the lungs; and increasing the beneficial antioxidant glutathione (which is diminished in smokers). |
| Metabolism | Uremic toxins tend to accumulate in the blood either through dietary excess or through poor filtration by the kidneys. Most uremic toxins are metabolic waste products and are normally excreted in the urine or feces. |
| Toxicity Values | None |
| Lethal Dose | None |
| Carcinogenicity (IARC Classification) | No indication of carcinogenicity to humans (not listed by IARC). |
| Minimum Risk Level | None |
| Health Effects | Chronic exposure to uremic toxins can lead to a number of conditions including renal damage, chronic kidney disease and cardiovascular disease. |
| Treatment | Kidney dialysis is usually needed to relieve the symptoms of uremic syndrome until normal kidney function can be restored. |
| Reference |
|
From T3DB
Taxonomic Classification
| Kingdom | Organic compounds |
|---|---|
| Superclass | Organic acids and derivatives |
| Class | Carboxylic acids and derivatives |
| Subclass | Amino acids, peptides, and analogues |
| Intermediate Tree Nodes | Amino acids and derivatives - Alpha amino acids and derivatives |
| Direct Parent | Cysteine and derivatives |
| Alternative Parents | |
| Molecular Framework | Aliphatic acyclic compounds |
| Substituents | Cysteine or derivatives - Alpha-amino acid - L-alpha-amino acid - Amino acid - Alkylthiol - Carboxylic acid - Monocarboxylic acid or derivatives - Organic oxygen compound - Primary amine - Organosulfur compound - Organooxygen compound - Organonitrogen compound - Organic nitrogen compound - Primary aliphatic amine - Carbonyl group - Amine - Hydrocarbon derivative - Organopnictogen compound - Organic oxide - Aliphatic acyclic compound |
| Description | This compound belongs to the class of organic compounds known as cysteine and derivatives. These are compounds containing cysteine or a derivative thereof resulting from reaction of cysteine at the amino group or the carboxy group, or from the replacement of any hydrogen of glycine by a heteroatom. |
From ClassyFire
Targets
- General Function:
- Ferrous iron binding
- Specific Function:
- Initiates several important metabolic pathways related to pyruvate and several sulfurate compounds including sulfate, hypotaurine and taurine. Critical regulator of cellular cysteine concentrations. Has an important role in maintaining the hepatic concentation of intracellular free cysteine within a proper narrow range.
- Gene Name:
- CDO1
- Uniprot ID:
- Q16878
- Molecular Weight:
- 22971.745 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Pyridoxal phosphate binding
- Specific Function:
- Catalyzes the last step in the trans-sulfuration pathway from methionine to cysteine. Has broad substrate specificity. Converts cystathionine to cysteine, ammonia and 2-oxobutanoate. Converts two cysteine molecules to lanthionine and hydrogen sulfide. Can also accept homocysteine as substrate. Specificity depends on the levels of the endogenous substrates. Generates the endogenous signaling molecule hydrogen sulfide (H2S), and so contributes to the regulation of blood pressure. Acts as a cysteine-protein sulfhydrase by mediating sulfhydration of target proteins: sulfhydration consists of converting -SH groups into -SSH on specific cysteine residues of target proteins such as GAPDH, PTPN1 and NF-kappa-B subunit RELA, thereby regulating their function.
- Gene Name:
- CTH
- Uniprot ID:
- P32929
- Molecular Weight:
- 44507.64 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Thiamine uptake transmembrane transporter activity
- Specific Function:
- Mediates high affinity thiamine uptake, propably via a proton anti-port mechanism. Has no folate transport activity.
- Gene Name:
- SLC19A3
- Uniprot ID:
- Q9BZV2
- Molecular Weight:
- 55664.265 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Protein kinase binding
- Specific Function:
- Motor protein required for establishing a bipolar spindle. Blocking of KIF11 prevents centrosome migration and arrest cells in mitosis with monoastral microtubule arrays.
- Gene Name:
- KIF11
- Uniprot ID:
- P52732
- Molecular Weight:
- 119158.025 Da
References
- Ogo N, Oishi S, Matsuno K, Sawada J, Fujii N, Asai A: Synthesis and biological evaluation of L-cysteine derivatives as mitotic kinesin Eg5 inhibitors. Bioorg Med Chem Lett. 2007 Jul 15;17(14):3921-4. Epub 2007 May 3. [17524640 ]
- General Function:
- Methyltransferase activity
- Specific Function:
- Involved in the cellular defense against the biological effects of O6-methylguanine (O6-MeG) in DNA. Repairs alkylated guanine in DNA by stoichiometrically transferring the alkyl group at the O-6 position to a cysteine residue in the enzyme. This is a suicide reaction: the enzyme is irreversibly inactivated.
- Gene Name:
- MGMT
- Uniprot ID:
- P16455
- Molecular Weight:
- 21645.83 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Ubiquitin protein ligase binding
- Specific Function:
- Hydro-lyase catalyzing the first step of the transsulfuration pathway, where the hydroxyl group of L-serine is displaced by L-homocysteine in a beta-replacement reaction to form L-cystathionine, the precursor of L-cysteine. This catabolic route allows the elimination of L-methionine and the toxic metabolite L-homocysteine (PubMed:23981774, PubMed:20506325, PubMed:23974653). Also involved in the production of hydrogen sulfide, a gasotransmitter with signaling and cytoprotective effects on neurons (By similarity).
- Gene Name:
- CBS
- Uniprot ID:
- P35520
- Molecular Weight:
- 60586.05 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Pyridoxal phosphate binding
- Specific Function:
- Catalyzes the removal of elemental sulfur from cysteine to produce alanine. It supplies the inorganic sulfur for iron-sulfur (Fe-S) clusters. May be involved in the biosynthesis of molybdenum cofactor.
- Gene Name:
- NFS1
- Uniprot ID:
- Q9Y697
- Molecular Weight:
- 50195.21 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Pyridoxal phosphate binding
- Specific Function:
- Biosynthesis of L-glutamate from L-aspartate or L-cysteine. Important regulator of levels of glutamate, the major excitatory neurotransmitter of the vertebrate central nervous system. Acts as a scavenger of glutamate in brain neuroprotection. The aspartate aminotransferase activity is involved in hepatic glucose synthesis during development and in adipocyte glyceroneogenesis. Using L-cysteine as substrate, regulates levels of mercaptopyruvate, an important source of hydrogen sulfide. Mercaptopyruvate is converted into H(2)S via the action of 3-mercaptopyruvate sulfurtransferase (3MST). Hydrogen sulfide is an important synaptic modulator and neuroprotectant in the brain.
- Gene Name:
- GOT1
- Uniprot ID:
- P17174
- Molecular Weight:
- 46247.14 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Cystine:glutamate antiporter activity
- Specific Function:
- Sodium-independent, high-affinity exchange of anionic amino acids with high specificity for anionic form of cystine and glutamate.
- Gene Name:
- SLC7A11
- Uniprot ID:
- Q9UPY5
- Molecular Weight:
- 55422.44 Da
References
- Patel SA, Rajale T, O'Brien E, Burkhart DJ, Nelson JK, Twamley B, Blumenfeld A, Szabon-Watola MI, Gerdes JM, Bridges RJ, Natale NR: Isoxazole analogues bind the system xc- transporter: structure-activity relationship and pharmacophore model. Bioorg Med Chem. 2010 Jan 1;18(1):202-13. doi: 10.1016/j.bmc.2009.11.001. Epub 2009 Nov 10. [19932968 ]
- General Function:
- Glutamate-cysteine ligase catalytic subunit binding
- Gene Name:
- GCLM
- Uniprot ID:
- P48507
- Molecular Weight:
- 30726.745 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- L-proline transmembrane transporter activity
- Specific Function:
- Neutral amino acid/proton symporter. Has a pH-dependent electrogenic transport activity for small amino acids such as glycine, alanine and proline. Besides small apolar L-amino acids, it also recognize their D-enantiomers and selected amino acid derivatives such as gamma-aminobutyric acid (By similarity).
- Gene Name:
- SLC36A1
- Uniprot ID:
- Q7Z2H8
- Molecular Weight:
- 53075.045 Da
References
- Thondorf I, Voigt V, Schafer S, Gebauer S, Zebisch K, Laug L, Brandsch M: Three-dimensional quantitative structure-activity relationship analyses of substrates of the human proton-coupled amino acid transporter 1 (hPAT1). Bioorg Med Chem. 2011 Nov 1;19(21):6409-18. doi: 10.1016/j.bmc.2011.08.058. Epub 2011 Sep 5. [21955456 ]
- General Function:
- Vitamin d binding
- Specific Function:
- May have weak glycosidase activity towards glucuronylated steroids. However, it lacks essential active site Glu residues at positions 239 and 872, suggesting it may be inactive as a glycosidase in vivo. May be involved in the regulation of calcium and phosphorus homeostasis by inhibiting the synthesis of active vitamin D (By similarity). Essential factor for the specific interaction between FGF23 and FGFR1 (By similarity).The Klotho peptide generated by cleavage of the membrane-bound isoform may be an anti-aging circulating hormone which would extend life span by inhibiting insulin/IGF1 signaling.
- Gene Name:
- KL
- Uniprot ID:
- Q9UEF7
- Molecular Weight:
- 116179.815 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Superoxide-generating nadph oxidase activity
- Specific Function:
- Constitutive NADPH oxidase which generates superoxide intracellularly upon formation of a complex with CYBA/p22phox. Regulates signaling cascades probably through phosphatases inhibition. May function as an oxygen sensor regulating the KCNK3/TASK-1 potassium channel and HIF1A activity. May regulate insulin signaling cascade. May play a role in apoptosis, bone resorption and lipolysaccharide-mediated activation of NFKB. May produce superoxide in the nucleus and play a role in regulating gene expression upon cell stimulation. Isoform 3 is not functional. Isoform 5 and isoform 6 display reduced activity.Isoform 4: Involved in redox signaling in vascular cells. Constitutively and NADPH-dependently generates reactive oxygen species (ROS). Modulates the nuclear activation of ERK1/2 and the ELK1 transcription factor, and is capable of inducing nuclear DNA damage. Displays an increased activity relative to isoform 1.
- Gene Name:
- NOX4
- Uniprot ID:
- Q9NPH5
- Molecular Weight:
- 66930.995 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
- General Function:
- Sodium-independent organic anion transmembrane transporter activity
- Specific Function:
- Plays an important role in the excretion/detoxification of endogenous and exogenous organic anions, especially from the brain and kidney. Involved in the transport basolateral of steviol, fexofenadine. Transports benzylpenicillin (PCG), estrone-3-sulfate (E1S), cimetidine (CMD), 2,4-dichloro-phenoxyacetate (2,4-D), p-amino-hippurate (PAH), acyclovir (ACV) and ochratoxin (OTA).
- Gene Name:
- SLC22A8
- Uniprot ID:
- Q8TCC7
- Molecular Weight:
- 59855.585 Da
References
- Young GH, Wu VC: KLOTHO methylation is linked to uremic toxins and chronic kidney disease. Kidney Int. 2012 Apr;81(7):611-2. doi: 10.1038/ki.2011.461. [22419041 ]
From T3DB