| SolubleOther = soluble in [[ethanol]], [[pyridine]] <br> insoluble in [[ether]]
| pKa = 2.35 and 9.78
}}
| Section3 = {{Chembox Hazards
| EUIndex =
| FlashPt =
| Autoignition =
| LD50 = 2600 mg/kg (mouse, oral)
}}
}}
'''Glycine''' (abbreviated as '''Gly''' or '''G''')<ref>{{IUPAC-IUB amino acids 1983}}.</ref> is an [[organic compound]] with the [[chemical formula|formula]] NH<sub>2</sub>CH<sub>2</sub>COOH. With only two [[hydrogen]] atoms as its 'side chain', glycine is the smallest of the 20 [[amino acid]]s commonly found in [[protein]]s. Its codons are GGU, GGC, GGA, GGG.
Glycine is a colourless, sweet-tasting crystalline solid. It is unique among the [[proteinogenic amino acid]]s in that it is not [[chirality (chemistry)|chiral]]. It can fit into [[Hydrophile|hydrophilic]] or [[Hydrophobe|hydrophobic]] environments, due to its two hydrogen atom side chain.
==Production and key properties==
Glycine was discovered in 1820, by [[Henri Braconnot]] who boiled gelatin with sulfuric acid.<ref>{{cite book |author= R.H.A. Plimmer |editor= R.H.A. Plimmer & F.G. Hopkins |title= The chemical composition of the proteins |url= http://books.google.com/?id=7JM8AAAAIAAJ&pg=PA112 |accessdate= January 18, 2010 |edition= 2nd |series= Monographs on biochemistry |volume= Part I. Analysis |origyear= 1908 |year= 1912 |publisher= Longmans, Green and Co. |location= London|page= 82}}</ref>
{{NatOrganicBox
Glycine is manufactured industrially by treating [[chloroacetic acid]] with [[ammonia]]:<ref>{{OrgSynth | first1 = A. W. | last1 = Ingersoll | first2 = S. H. | last2 = Babcock | title = Hippuric acid | prep=cv2p0328 | volume = 12 | pages = 40 | year = 1932 | collvol = 2 | collvolpages = 328}}.</ref>
| image= [[Image:Glycin - Glycine.svg.png|105px|Skeletal formula of glycine]]<br>[[Image:Glycine-3D-balls.png|105px|Ball-and-stick model of the glycine molecule]][[Image:Glycine-3D-vdW.png|105px|Space-filling model of the glycine molecule]]
About 15M kg are produced annually in this way.<ref>Karlheinz Drauz, Ian Grayson, Axel Kleemann, Hans-Peter Krimmer, Wolfgang Leuchtenberger, Christoph Weckbecker “Amino Acids” in Ullmann's Encyclopedia of Industrial Chemistry 2007, Wiley-VCH, Weinheim. {{DOI|10.1002/14356007.a02_057.pub2}}</ref>
| PubChem = 750
| CAS = 56-40-6
| SMILES = NCC(O)=O
| C=2 | H=5 | N=1 | O=2
| mass=75.07 g/mol
}}
{{EH}}
{{SI}}
==Overview==
In the USA (by GEO Specialty Chemicals, Inc.) and in Japan (by Shoadenko), glycine is produced via the [[Strecker amino acid synthesis]].<ref name="usitc.gov">http://www.usitc.gov/trade_remedy/731_ad_701_cvd/investigations/2007/glycine_from_india_japan_korea/preliminary/DOC/Glycine%20Conference%20(prelim).wpd</ref>
'''Glycine''' (abbreviated as '''Gly''' or '''G''')<ref>{{cite web | author=IUPAC-IUBMB Joint Commission on Biochemical Nomenclature | title=Nomenclature and Symbolism for Amino Acids and Peptides | work=Recommendations on Organic & Biochemical Nomenclature, Symbols & Terminology etc | url=http://www.chem.qmul.ac.uk/iupac/AminoAcid/ | accessdate=2007-05-17}}</ref> is the [[organic compound]] with the [[chemical formula|formula]] HO<sub>2</sub>CCH<sub>2</sub>NH<sub>2</sub>. It is one of the 20 [[amino acid]]s commonly found in [[protein]]s, coded by [[codons]] GGU, GGC, GGA and GGG. Because of its structural simplicity, this compact amino acid tends to be evolutionarily conserved in, for example, [[cytochrome c]], [[myoglobin]], and [[hemoglobin]]. Glycine is the unique amino acid that is not [[optical isomerism|optically active]]. Most proteins contain only small quantities of glycine. A notable exception is [[collagen]], which contains about 35% glycine.<ref name=Nel127>Nelson, D. L. & Cox, M. M. (2005). ''Lehninger Principles of Biochemistry'', 4th Edition. New York: W. H. Freeman and Company, p. 127. ISBN 0-7167-4339-6.</ref> In its solid, i.e., crystallized, form, Glycine is a free-flowing crystalline
material. <ref name=72FR62827>"Notice of Preliminary Determination of Sales at Less Than Fair
Value: Glycine From India" Federal Register 72 (7 November 2007): 62827.</ref>
==Synthesis==
There are two producers of glycine in the United States. Chattem Chemicals, Inc., purchased by Sun Pharmaceutical, who is an international pharmaceutical company based in Mumbai, India and GEO Specialty Chemicals, Inc., who purchased the glycine and naphthalene sulfonate production facilities of Dow/Hampshire Chemical Corp.<ref name="usitc.gov"/><ref>U.S. International Trade Commission, "Glycine From China." Investigation No. 731-TA-718 (Second Review), Publication No. 3810, October 2005</ref>
Glycine is manufactured industrially: (1)treatment of [[chloroacetic acid]] with ammonia leads to the product in one step.
and (2)The Strecker Synthesis via hydrolysis of a nitrile.
Chattem's manufacturing process ("MCA" process) occurs in batches and results in a finished product with some residual chloride but no sulfate, while GEO’s manufacturing process is considered a semi-batch process and results in a finished product with some residual sulfate but no chloride.
There are two producers of Glycine in the United States. Chattem Chemicals, Inc. and GEO Specialty Chemicals, Inc. (which purchased the Glycine production facilities of Hampshire Chemical Corp.<ref name=usitc3810>U.S. International Trade Commission, "Glycine From China." Investigation No. 731-TA-718 (Second Review), Publication No. 3810, October 2005</ref> <ref name=Ham110105>Nov. 1, 2005 Press Release [http://news.dow.com/dow_news/prodbus/2005/20051101e.htm]</ref> According to information provided to the U.S. Department of Commerce, each uses a different manufacturing process and different raw materials. Chattem's manufacturing process (the "MCA" process) occurs in batches and results in a finished product with some residual chloride but no sulfate, while GEO’s manufacturing process is considered a semi-batch process and results in a finished product with some residual sulfate but no chloride.<ref name=usitc3810>U.S. International Trade Commission, "Glycine From China." Investigation No. 731-TA-718 (Second Review), Publication No. 3810, October 2005</ref>
Its pK values are 2.35 and 9.78, so above pH 9.78, most of the glycine exists as the anionic amine, H<sub>2</sub>NCH<sub>2</sub>CO<sub>2</sub><sup>-</sup>. Below pH 2.35, its solutions contain mostly the cationic carboxylic acid H<sub>3</sub>N<sup>+</sup>CH<sub>2</sub>CO<sub>2</sub>H. Its [[isoelectric point]] (pI) is 6.06.
==Biosynthesis==
==Biosynthesis==
Glycine is not essential to the human diet, since it is biosynthesized in the body from the amino acid [[serine]], which is in turn derived from [[3-phosphoglycerate]]. In most organisms, the enzyme [[Serine hydroxymethyltransferase]] catalyses this transformation by removing one carbon atom; [[pyridoxal phosphate]] is also necessary:<ref name=Nel844>Nelson, D. L. & Cox, M. M. (2005). ''Lehninger Principles of Biochemistry'', 4th Edition. New York: W. H. Freeman and Company, p. 844. ISBN 0-7167-4339-6.</ref>
Glycine is not essential to the human diet, as it is biosynthesized in the body from the amino acid [[serine]], which is in turn derived from [[3-phosphoglycerate]]. In most organisms, the enzyme [[Serine hydroxymethyltransferase]] catalyses this transformation via the cofactor [[pyridoxal phosphate]]:<ref name="Lehninger"/>
In the liver of [[vertebrates]], glycine synthesis is catalyzed by [[glycine synthase]] (also called glycine cleavage enzyme). This conversion is readily reversible:<ref name="Lehninger"/>
In the liver of [[vertebrates]], glycine synthesis is catalyzed by glycine synthase (also called glycine cleavage enzyme). This conversion is readily reversible:<ref name=Nel844/>
Glycine is coded by [[codons]] GGU, GGC, GGA and GGG. Most proteins incorporate only small quantities of glycine. A notable exception is [[collagen]], which contains about 35% glycine.<ref name="Lehninger">{{Lehninger4th|pages=127, 675–77, 844, 854}}.</ref>
Glycine is degraded via three pathways. The predominant pathway in animals involves the catalysis of [[glycine cleavage enzyme]], the same enzyme also involved in the biosynthesis of glycine. The degradation pathway is the reverse of this synthetic pathway:<ref name=Nel675>Nelson, D. L. & Cox, M. M. (2005). ''Lehninger Principles of Biochemistry'', 4th Edition. New York: W. H. Freeman and Company, pp. 675-677. ISBN 0-7167-4339-6.</ref>
Glycine is degraded via three pathways. The predominant pathway in animals involves the catalysis of [[glycine cleavage enzyme]], the same enzyme also involved in the biosynthesis of glycine. The degradation pathway is the reverse of this synthetic pathway:<ref name="Lehninger"/>
In the second pathway, glycine is degraded in two steps. The first step is the reverse of glycine biosynthesis from serine with serine hydroxymethyl transferase. Serine is then converted to [[pyruvate]] by [[serine dehydratase]].<ref name=Nel675/>
In the second pathway, glycine is degraded in two steps. The first step is the reverse of glycine biosynthesis from serine with serine hydroxymethyl transferase. Serine is then converted to [[pyruvate]] by [[serine dehydratase]].<ref name="Lehninger"/>
In the third pathway of glycine degradation, glycine is converted to glyoxylate by [[D-amino acid oxidase]]. Glycoxylate is then oxidized by hepatic [[lactate dehydrogenase]] to [[oxalate]] in an NAD<sup>+</sup>-dependent reaction.<ref name=Nel675/>
In the third pathway of glycine degradation, glycine is converted to [[glyoxylate]] by [[D-amino acid oxidase]]. Glyoxylate is then oxidized by hepatic [[lactate dehydrogenase]] to [[oxalate]] in an NAD<sup>+</sup>-dependent reaction.<ref name="Lehninger"/>
==Physiological function==
==Physiological function==
The principal function of glycine is as a precursor to proteins. It is also a building block to numerous natural products.
===As a biosynthetic intermediate===
===As a biosynthetic intermediate===
Glycine is a building block to numerous natural products. In higher [[eukaryotes]], [[D-Aminolevulinic acid]], the key precursor to [[porphyrins]], is biosynthesized from glycine and [[succinyl-CoA]]. Glycine provides the central C<sub>2</sub>N subunit of all [[purine]]s.<ref name=Nel854>Nelson, D. L. & Cox, M. M. (2005). ''Lehninger Principles of Biochemistry'', 4th Edition. New York: W. H. Freeman and Company, p. 854. ISBN 0-7167-4339-6.</ref>
In higher [[eukaryotes]], [[D-Aminolevulinic acid]], the key precursor to [[porphyrins]], is biosynthesized from glycine and [[succinyl-CoA]]. Glycine provides the central C<sub>2</sub>N subunit of all [[purine]]s.<ref name="Lehninger"/>
===As a neurotransmitter===
===As a neurotransmitter===
Glycine is an inhibitory [[neurotransmitter]] in the [[central nervous system]], especially in the [[spinal cord]], brainstem, and retina. When glycine receptors are activated, chloride enters the neuron via ionotropic receptors, causing an [[Inhibitory postsynaptic potential]] (IPSP). [[Strychnine]] is an antagonist at ionotropic glycine receptors. Glycine is a required co-agonist along with [[glutamate]] for [[NMDA receptor]]s. In contrast to the inhibitory role of glycine in the spinal cord, this behaviour is facilitated at the ([[NMDA]]) glutaminergic receptors which are excitatory. The [[LD50|LD<sub>50</sub>]] of glycine is 7930 mg/kg in rats (oral),<ref>{{cite web |url=http://physchem.ox.ac.uk/MSDS/GL/glycine.html |title=Safety (MSDS) data for glycine |date=2005 |publisher= The Physical and Theoretical Chemistry Laboratory Oxford University |accessdate=2006-11-01}}</ref> and it usually causes death by hyperexcitability.
Glycine is an inhibitory [[neurotransmitter]] in the [[central nervous system]], especially in the [[spinal cord]], brainstem, and retina. When [[glycine receptors]] are activated, [[chloride]] enters the neuron via ionotropic receptors, causing an [[Inhibitory postsynaptic potential]] (IPSP). [[Strychnine]] is a strong antagonist at ionotropic glycine receptors, whereas [[bicuculline]] is a weak one. Glycine is a required [[co-agonist]] along with [[glutamate]] for [[NMDA receptor]]s. In contrast to the inhibitory role of glycine in the spinal cord, this behaviour is facilitated at the ([[NMDA]]) glutaminergic receptors which are excitatory.{{Citation needed|date=June 2009}} The {{LD50}} of glycine is 7930 mg/kg in rats (oral),<ref>{{cite web |url=http://physchem.ox.ac.uk/MSDS/GL/glycine.html |title=Safety (MSDS) data for glycine |year=2005 |publisher= The Physical and Theoretical Chemistry Laboratory Oxford University |accessdate=2006-11-01}}</ref> and it usually causes death by [[hyperexcitability]].
==Industrial Uses==
==Commercial uses==
In the US, glycine is typically sold in two grades: [[United States Pharmacopeia]] (“USP”), and technical grade. Most glycine is manufactured as USP grade material for diverse uses. USP grade sales account for approximately 80 to 85 percent of the U.S. market for glycine.
* Pharmaceutical grade glycine is produced for some pharmaceutical applications, such as intravenous injections, where the customer’s purity requirements often exceed the minimum required under the USP grade designation. Pharmaceutical grade glycine is often produced to proprietary specifications and is typically sold at a premium over USP grade glycine.
* Technical grade glycine, which may or may not meet USP grade standards, is sold for use in industrial applications; e.g., as an agent in metal complexing and finishing. Technical grade glycine is typically sold at a discount to USP grade glycine.<ref>http://hotdocs.usitc.gov/docs/pubs/701_731/pub3921.pdf</ref>
Glycine is used as a sweetener/taste enhancer, buffering agent, reabsorbable amino acid, chemical intermediate, metal complexing agent, dietary supplement as well as in certain pharmaceuticals. <ref name=72FR62827>"Notice of Preliminary Determination of Sales at Less Than Fair Value: Glycine From India" Federal Register 72 (7 November 2007): 62827.</ref>
===Animal and human foods===
Other markets for USP grade glycine include its use an additive in [[pet food]] and [[compound feed|animal feed]]. For humans, glycine is sold as a sweetener/taste enhancer. Food supplements and protein drinks contain glycine. Certain drug formulations include glycine to improve gastric absorption of the drug.
==Antidumping Tarrifs==
===Cosmetics and miscellaneous applications===
Glycine serves as a [[buffering agent]] in [[antacids]], [[analgesics]], [[antiperspirants]], cosmetics, and toiletries.
Glycine imported from China to the United States has been subject to antidumping duties since March, 1995. <ref name=usitc2863> Glycine from the People’s Republic of China, Inv. No. 731-TA-718 (Final), USITC Pub. 2863 (Mar. 1995)
Many miscellaneous products use glycine or its derivatives, such as the production of rubber sponge products, fertilizers, metal complexants.<ref name=72FR62827>"Notice of Preliminary Determination of Sales at Less Than Fair Value: Glycine From India" Federal Register 72 (7 November 2007): 62827.</ref>
(“Original Determination”) at 1.</ref>
In 2007, a United States manufacturer of Glycine, GEO Specialty Chemicals, Inc. filed petitions requesting that antidumping duties also be imposed on Glycine imported from China, Japan, the Republic of Korea, and India. On September 7, 2007 the Department of Commerce announced its affirmative preliminary determinations in the antidumping duty investigations on imports of glycine from Japan and the Republic of Korea (Korea). On October 29, 2007 the Department of Commerce announced its affirmative preliminary determination in the antidumping duty investigation on imports of glycine from India.
[[File:Betain-Glycine.png|thumb|right|300px|Zwitterionic salts of glycine at neutral pH]]
==Presence in the interstellar medium==
===Chemical feedstock===
In 1994 a team of astronomers at the [[University of Illinois at Urbana-Champaign|University of Illinois]], led by [[Lewis Snyder]], claimed that they had found the glycine molecule in space. It turned out that, with further analysis, this claim could not be confirmed. Nine years later, in 2003, [[Yi-Jehng Kuan]] from [[National Taiwan Normal University]] and [[Steve Charnley]] claimed that they detected interstellar glycine toward three sources in the [[interstellar medium]].<ref name=Kuan>{{cite journal |author=Kuan YJ, Charnley SB, Huang HC, et al. |title=Interstellar glycine |journal=ASTROPHYS J |volume=593 |issue=2 |pages=848-867 |year=2003 |doi=10.1086/375637}}</ref> They claimed to have identified 27 [[spectral]] lines of glycine utilizing a [[radio telescope]]. According to computer simulations and lab-based experiments, glycine was probably formed when ices containing simple organic molecules were exposed to [[ultraviolet light]].<ref>{{cite web |url=http://www.newscientist.com/news/news.jsp?id=ns99992558 |author=Rachel Nowak |title=Amino acid found in deep space - 18 July 2002 - New Scientist |accessdate=2007-07-01}}</ref>
Glycine is an intermediate in the synthesis of a variety of chemical products. It is used in the manufacture of the herbicide [[Glyphosate]]. Glyphosate (N-(phosphonomethyl) glycine) is a non-selective systemic herbicide used to kill weeds, especially perennials and broadcast or used in the cut-stump treatment as a forestry herbicide. Initially, Glyphosate was sold only by Monsanto under the Monsanto tradename [[Roundup]], but is no longer under patent.
In October 2004, Snyder and collaborators reinvestigated the glycine claim in Kuan ''et al.'' (2003). In a rigorous attempt to confirm the detection, Snyder showed that glycine was not detected in any of the three claimed sources.<ref name=Snyder>{{cite journal |author=Snyder LE, Lovas FJ, Hollis JM, et al. |title=A rigorous attempt to verify interstellar glycine |journal=ASTROPHYS J |volume=619 |issue=2 |pages=914-930 |year=2005 |doi=10.1086/426677}}</ref>
==Presence in space==
The detection of glycine in the [[interstellar medium]] has been debated.<ref name=Snyder>{{cite journal |author=Snyder LE, Lovas FJ, Hollis JM, et al. |title=A rigorous attempt to verify interstellar glycine |journal=Astrophys J |volume=619 |issue=2 |pages=914–930 |year=2005 |doi=10.1086/426677}}</ref> In 2008, the glycine-like molecule [[aminoacetonitrile]] was discovered in the [[Large Molecule Heimat]], a giant gas cloud near the galactic center in the constellation [[Sagittarius (constellation)|Sagittarius]] by the [[Max Planck Institute for Radio Astronomy]].<ref>{{cite web |url=http://www.sciencedaily.com/releases/2008/03/080326161658.htm |author=Staff|title=Organic Molecule, Amino Acid-Like, Found In Constellation Sagittarius 27 March 2008 - Science Daily |accessdate=2008-09-16}}</ref> In 2009, glycine sampled in 2004 from comet [[Wild 2]] by the [[NASA]] spacecraft [[Stardust (spacecraft)|Stardust]] was confirmed, the first discovery of extraterrestrial glycine. That mission's results bolstered the theory of [[panspermia]], which claims that the "seeds" of life are widespread throughout the universe.<ref>{{cite news |url=http://www.reuters.com/article/scienceNews/idUSTRE57H02I20090818 |author=Reuters|title=Building block of life found on comet - Thomson Reuters 2009 |accessdate=2009-08-18 | date=18 August 2009}}</ref>
Should the glycine claim be substantiated, the finding would not prove that life exists outside the [[Earth]], but certainly makes that possibility more plausible by showing that amino acids can be formed in the interstellar medium.
== See also ==
* [[Trimethylglycine]]
==References==
== References ==
{{reflist}}
{{Reflist|2}}
* Dawson, R.M.C., Elliott, D.C., Elliott, W.H., and Jones, K.M., ''Data for Biochemical Research'' (3rd edition), pp. 1-31 (1986) ISBN 01-985-535-87
==Further reading==
On attempts to detect glycine in interstellar medium
*{{cite web |url=http://www.newscientist.com/news/news.jsp?id=ns99992558 |author=Rachel Nowak |title=Amino acid found in deep space - 18 July 2002 - New Scientist |accessdate=2007-07-01}}
* [http://www.schizophrenia.com/glycinetreat.htm Glycine Therapy - A New Direction for Schizophrenia Treatment?]
* {{cite journal | title = Organic Molecule, Amino Acid-Like, Found In Constellation Sagittarius | journal = ScienceDaily |date=27 March 2008| url = http://www.sciencedaily.com/releases/2008/03/080326161658.htm}}
* {{cite journal | journal = Psychiatric Times | volume = 25 | issue = 14 | title = A New Class of Antipsychotic Drugs: Enhancing Neurotransmission Mediated by NMDA Receptors | author = Guochuan E. Tsai |date=1 December 2008| url = http://www.psychiatrictimes.com/display/article/10168/1357569}}
* [http://www.jpl.nasa.gov/news/news.cfm?release=2009-126 NASA scientists have discovered glycine, a fundamental building block of life, in samples of comet Wild 2 returned by NASA's Stardust spacecraft.]
Glycine (abbreviated as Gly or G)[2] is an organic compound with the formula NH2CH2COOH. With only two hydrogen atoms as its 'side chain', glycine is the smallest of the 20 amino acids commonly found in proteins. Its codons are GGU, GGC, GGA, GGG.
Glycine is a colourless, sweet-tasting crystalline solid. It is unique among the proteinogenic amino acids in that it is not chiral. It can fit into hydrophilic or hydrophobic environments, due to its two hydrogen atom side chain.
About 15M kg are produced annually in this way.[5]
In the USA (by GEO Specialty Chemicals, Inc.) and in Japan (by Shoadenko), glycine is produced via the Strecker amino acid synthesis.[6]
There are two producers of glycine in the United States. Chattem Chemicals, Inc., purchased by Sun Pharmaceutical, who is an international pharmaceutical company based in Mumbai, India and GEO Specialty Chemicals, Inc., who purchased the glycine and naphthalene sulfonate production facilities of Dow/Hampshire Chemical Corp.[6][7]
Chattem's manufacturing process ("MCA" process) occurs in batches and results in a finished product with some residual chloride but no sulfate, while GEO’s manufacturing process is considered a semi-batch process and results in a finished product with some residual sulfate but no chloride.
Its pK values are 2.35 and 9.78, so above pH 9.78, most of the glycine exists as the anionic amine, H2NCH2CO2-. Below pH 2.35, its solutions contain mostly the cationic carboxylic acid H3N+CH2CO2H. Its isoelectric point (pI) is 6.06.
In the liver of vertebrates, glycine synthesis is catalyzed by glycine synthase (also called glycine cleavage enzyme). This conversion is readily reversible:[8]
Glycine is coded by codons GGU, GGC, GGA and GGG. Most proteins incorporate only small quantities of glycine. A notable exception is collagen, which contains about 35% glycine.[8]
Degradation
Glycine is degraded via three pathways. The predominant pathway in animals involves the catalysis of glycine cleavage enzyme, the same enzyme also involved in the biosynthesis of glycine. The degradation pathway is the reverse of this synthetic pathway:[8]
In the second pathway, glycine is degraded in two steps. The first step is the reverse of glycine biosynthesis from serine with serine hydroxymethyl transferase. Serine is then converted to pyruvate by serine dehydratase.[8]
In the US, glycine is typically sold in two grades: United States Pharmacopeia (“USP”), and technical grade. Most glycine is manufactured as USP grade material for diverse uses. USP grade sales account for approximately 80 to 85 percent of the U.S. market for glycine.
Pharmaceutical grade glycine is produced for some pharmaceutical applications, such as intravenous injections, where the customer’s purity requirements often exceed the minimum required under the USP grade designation. Pharmaceutical grade glycine is often produced to proprietary specifications and is typically sold at a premium over USP grade glycine.
Technical grade glycine, which may or may not meet USP grade standards, is sold for use in industrial applications; e.g., as an agent in metal complexing and finishing. Technical grade glycine is typically sold at a discount to USP grade glycine.[10]
Animal and human foods
Other markets for USP grade glycine include its use an additive in pet food and animal feed. For humans, glycine is sold as a sweetener/taste enhancer. Food supplements and protein drinks contain glycine. Certain drug formulations include glycine to improve gastric absorption of the drug.
Glycine is an intermediate in the synthesis of a variety of chemical products. It is used in the manufacture of the herbicide Glyphosate. Glyphosate (N-(phosphonomethyl) glycine) is a non-selective systemic herbicide used to kill weeds, especially perennials and broadcast or used in the cut-stump treatment as a forestry herbicide. Initially, Glyphosate was sold only by Monsanto under the Monsanto tradename Roundup, but is no longer under patent.
↑R.H.A. Plimmer (1912) [1908]. R.H.A. Plimmer & F.G. Hopkins, ed. The chemical composition of the proteins. Monographs on biochemistry. Part I. Analysis (2nd ed.). London: Longmans, Green and Co. p. 82. Retrieved January 18, 2010.
↑Karlheinz Drauz, Ian Grayson, Axel Kleemann, Hans-Peter Krimmer, Wolfgang Leuchtenberger, Christoph Weckbecker “Amino Acids” in Ullmann's Encyclopedia of Industrial Chemistry 2007, Wiley-VCH, Weinheim. doi:10.1002/14356007.a02_057.pub2
↑"Notice of Preliminary Determination of Sales at Less Than Fair Value: Glycine From India" Federal Register 72 (7 November 2007): 62827.
↑Snyder LE, Lovas FJ, Hollis JM; et al. (2005). "A rigorous attempt to verify interstellar glycine". Astrophys J. 619 (2): 914–930. doi:10.1086/426677.CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link)
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