Glycine

For other uses, see Glycine (disambiguation).
Not to be confused with Glycerin.

Glycine[1]
Skeletal formula of neutral glycine
Skeletal formula of zwitterionic glycine
Ball-and-stick model of the gas-phase structure
Ball-and-stick model of the zwitterionic solid-state structure
Space-filling model of the gas-phase structure
Space-filling model of the zwitterionic solid-state structure
Names
IUPAC name
Glycine
Systematic IUPAC name
Aminoacetic acid[2]
Other names
  • 2-Aminoethanoic acid
  • Glycocol
  • Glycic acid
  • Dicarbamic acid
Identifiers
3D model (JSmol)
Abbreviations Gly, G
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.000.248 Edit this at Wikidata
EC Number
  • 200-272-2
  • 227-841-8
E number E640 (flavour enhancer)
KEGG
UNII
  • InChI=1S/C2H5NH2/c3-1-2(4)5/h1,3H2,(H,4,5) checkY
    Key: DHMQDGOQFOQNFH-UHFFFAOYSA-N checkY
  • InChI=1S/C2H5NO2/c3-1-2(4)5/h1,3H2,(H,4,5)
    Key: DHMQDGOQFOQNFH-UHFFFAOYAW
  • C(C(=O)O)N
  • Zwitterion: C(C(=O)[O-])[NH3+]
  • C(C(=O)O)N.Cl
Properties
C2H5NO2
Molar mass 75.067 g·mol−1
Appearance White solid
Density 1.1607 g/cm3[3]
Melting point 233 °C (451 °F; 506 K) (decomposition)
249.9 g/L (25 °C)[4]
Solubility soluble in pyridine
sparingly soluble in ethanol
insoluble in ether
Acidity (pKa) 2.34 (carboxyl), 9.6 (amino)[5]
-40.3·10−6 cm3/mol
Pharmacology
B05CX03 (WHO)
Hazards
Lethal dose or concentration (LD, LC):
2600 mg/kg (mouse, oral)
Supplementary data page
Glycine (data page)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Glycine (symbol Gly or G;[6] /ˈɡlaɪsiːn/ ⓘ)[7] is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable). Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG).[8] Glycine is integral to the formation of alpha-helices in secondary protein structure due to the "flexibility" caused by such a small R group. Glycine is also an inhibitory neurotransmitter[9] – interference with its release within the spinal cord (such as during a Clostridium tetani infection) can cause spastic paralysis due to uninhibited muscle contraction.[10]

It is the only achiral proteinogenic amino acid.[11] It can fit into hydrophilic or hydrophobic environments, due to its minimal side chain of only one hydrogen atom.[12]

  1. ^ The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals (11th ed.), Merck, 1989, ISBN 091191028X, 4386
  2. ^ "Glycine". PubChem.
  3. ^ Handbook of Chemistry and Physics, CRC Press, 59th edition, 1978.[page needed]
  4. ^ "Solubilities and densities". Prowl.rockefeller.edu. Archived from the original on September 12, 2017. Retrieved November 13, 2013.
  5. ^ Dawson, R.M.C., et al., Data for Biochemical Research, Oxford, Clarendon Press, 1959.[page needed]
  6. ^ "Nomenclature and Symbolism for Amino Acids and Peptides". IUPAC-IUB Joint Commission on Biochemical Nomenclature. 1983. Archived from the original on October 9, 2008. Retrieved March 5, 2018.
  7. ^ "Glycine | Definition of glycine in English by Oxford Dictionaries". Archived from the original on January 29, 2018.
  8. ^ Pawlak K, Błażej P, Mackiewicz D, Mackiewicz P (January 2023). "The Influence of the Selection at the Amino Acid Level on Synonymous Codon Usage from the Viewpoint of Alternative Genetic Codes". International Journal of Molecular Sciences. 24 (2): 1185. doi:10.3390/ijms24021185. PMC 9866869. PMID 36674703.
  9. ^ Zafra F, Aragón C, Giménez C (June 1997). "Molecular biology of glycinergic neurotransmission". Molecular Neurobiology. 14 (3): 117–142. doi:10.1007/BF02740653. PMID 9294860.
  10. ^ Atchison W (2018). "Toxicology of the Neuromuscular Junction". Comprehensive Toxicology. pp. 259–282. doi:10.1016/B978-0-12-801238-3.99198-0. ISBN 978-0-08-100601-6.
  11. ^ Matsumoto A, Ozaki H, Tsuchiya S, Asahi T, Lahav M, Kawasaki T, et al. (April 2019). "Achiral amino acid glycine acts as an origin of homochirality in asymmetric autocatalysis". Organic & Biomolecular Chemistry. 17 (17): 4200–4203. doi:10.1039/C9OB00345B. PMID 30932119.
  12. ^ Alves A, Bassot A, Bulteau AL, Pirola L, Morio B (June 2019). "Glycine Metabolism and Its Alterations in Obesity and Metabolic Diseases". Nutrients. 11 (6): 1356. doi:10.3390/nu11061356. PMC 6627940. PMID 31208147.