Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Coenzyme A: Difference between pages

{{short description|Coenzyme, notable for its synthesis and oxidation role}}

| verifiedrevid = 476994860

| Name =

| ImageFile = Coenzym A.svg

| ImageSize = 350px

| ImageFile3 = Coenzyme-A-3D-vdW.png

| ImageSize3 = 350px

| IUPACName =

| OtherNames =

| SystematicName = [(2R,3S,4R,5R)-5-(6-Amino-9H-purin-9-yl)-4-hydroxy-3-(phosphonooxy)tetrahydro-2-furanyl]methyl (3R)-3-hydroxy-2,2-dimethyl-4-oxo-4-({3-oxo-3-[(2-sulfanylethyl)amino]propyl}amino)butyl dihydrogen diphosphate

| Section1 = {{Chembox Identifiers

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| ChEMBL = 1213327

| ChEBI = 15346

| CASNo_Comment = (free acid)

| CASNo2_Ref = {{cascite|unknown|CAS}}

| CASNo2 = 55672-92-9

| CASNo2_Comment = (sodium salt hydrate)

| CASNo3_Ref = {{cascite|unknown|CAS}}

| CASNo3 = 18439-24-2

| CASNo3_Comment = (lithium salt)

| PubChem = 6816

| DrugBank_Ref = {{drugbankcite|correct|drugbank}}

| MeSHName = Coenzyme+A

| Section2 = {{Chembox Properties

| Formula = C₂₁H₃₆N₇O₁₆P₃S

| MolarMass = 767.535

| Appearance =

| Density =

| MeltingPt =

| BoilingPt =

| LambdaMax = 259.5 nm<ref name="Dawson_2002">{{cite book | vauthors = Dawson RM, Elliott DC, Elliott WH, Jones KM |title=Data for Biochemical Research |date=2002 |publisher=Clarendon Press |isbn=978-0-19-855299-4 |edition=3rd|pages=118–119}}</ref>

| Absorbance = [[Molar attenuation coefficient|ε₂₅₉]] = 16.8 mM⁻¹ cm⁻¹<ref name="Dawson_2002" />

| Section3 = {{Chembox Hazards

| MainHazards =

| FlashPt =

| AutoignitionPt =

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'''Coenzyme A''' ('''CoA''', '''SHCoA''', '''CoASH''') is a [[coenzyme]], notable for its role in the [[Fatty acid metabolism#Synthesis|synthesis]] and [[Fatty acid metabolism#.CE.B2-Oxidation|oxidation]] of [[fatty acid]]s, and the oxidation of [[pyruvic acid|pyruvate]] in the [[citric acid cycle]]. All [[genome]]s sequenced to date encode enzymes that use coenzyme A as a [[Substrate (chemistry)|substrate]], and around 4% of cellular enzymes use it (or a [[thioester]]) as a substrate. In humans, CoA biosynthesis requires [[cysteine]], [[pantothenic acid|pantothenate]] (vitamin B₅), and [[adenosine triphosphate]] (ATP).<ref>{{cite journal | vauthors = Daugherty M, Polanuyer B, Farrell M, Scholle M, Lykidis A, de Crécy-Lagard V, Osterman A | title = Complete reconstitution of the human coenzyme A biosynthetic pathway via comparative genomics | journal = The Journal of Biological Chemistry | volume = 277 | issue = 24 | pages = 21431–21439 | date = June 2002 | pmid = 11923312 | doi = 10.1074/jbc.M201708200 | doi-access = free }}</ref>

In [[acetyl-CoA|its acetyl form]], coenzyme A is a highly versatile molecule, serving metabolic functions in both the [[Anabolism|anabolic]] and [[Catabolism|catabolic]] pathways. Acetyl-CoA is utilised in the [[post-translational regulation]] and [[allosteric regulation]] of [[pyruvate dehydrogenase]] and [[carboxylase]] to maintain and support the partition of [[Pyruvic acid|pyruvate]] synthesis and degradation.<ref>{{Cite web|url=http://www.asbmb.org/asbmbtoday/asbmbtoday_article.aspx?id=48246|title=Coenzyme A: when small is mighty|website=www.asbmb.org|access-date=2018-12-19|archive-url=https://web.archive.org/web/20181220033910/http://www.asbmb.org/asbmbtoday/asbmbtoday_article.aspx?id=48246|archive-date=2018-12-20|url-status=dead}}</ref>

==Discovery of structure==

[[File:Coenzym A beschriftet.svg|thumb|300 px|Structure of coenzyme A: 1: 3′-phosphoadenosine. 2: diphosphate, organophosphate anhydride. 3: pantoic acid. 4: β-alanine. 5: cysteamine.]]

Coenzyme A was identified by [[Fritz Lipmann]] in 1946,<ref>{{cite journal | vauthors = Lipmann F, Kaplan NO |title=A common factor in the enzymatic acetylation of sulfanilamide and of choline |journal=Journal of Biological Chemistry |date=1946 |volume=162 |issue=3 |pages=743–744 |doi=10.1016/S0021-9258(17)41419-0 |doi-access=free }}</ref> who also later gave it its name. Its structure was determined during the early 1950s at the [[Lister Institute]], London, together by Lipmann and other workers at [[Harvard Medical School]] and [[Massachusetts General Hospital]].<ref name="Nature">{{cite journal | vauthors = Baddiley J, Thain EM, Novelli GD, Lipmann F | title = Structure of coenzyme A | journal = Nature | volume = 171 | issue = 4341 | pages = 76 | date = January 1953 | pmid = 13025483 | doi = 10.1038/171076a0 | s2cid = 630898 | bibcode = 1953Natur.171...76B | doi-access = free }}</ref> Lipmann initially intended to study acetyl transfer in animals, and from these experiments he noticed a unique factor that was not present in enzyme extracts but was evident in all organs of the animals. He was able to isolate and purify the factor from pig liver and discovered that its function was related to a coenzyme that was active in choline acetylation.<ref name=":0">{{Cite journal | vauthors = Kresge N, Simoni RD, Hill RL |date=2005-05-27|title=Fritz Lipmann and the Discovery of Coenzyme A|url=http://www.jbc.org/content/280/21/e18|journal=Journal of Biological Chemistry|language=en|volume=280|issue=21|pages=e18|issn=0021-9258|access-date=2017-10-24|archive-date=2019-04-12|archive-url=https://web.archive.org/web/20190412153806/http://www.jbc.org/content/280/21/e18|url-status=dead}}</ref> Work with [[Beverly Guirard]], [[Nathan O. Kaplan|Nathan Kaplan]], and others determined that pantothenic acid was a central component of coenzyme A.<ref>{{cite journal | vauthors = Lipmann F, Kaplan NO | title = Coenzyme for acetylation, a pantothenic acid derivative | journal = The Journal of Biological Chemistry | volume = 167 | issue = 3 | pages = 869–870 | date = March 1947 | pmid = 20287921 | doi = 10.1016/S0021-9258(17)30973-0 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Lipmann F, Kaplan NO, Novelli GD, Tuttle LC, Guirard BM | title = Isolation of coenzyme A | journal = The Journal of Biological Chemistry | volume = 186 | issue = 1 | pages = 235–243 | date = September 1950 | pmid = 14778827 | doi = 10.1016/S0021-9258(18)56309-2 | doi-access = free }}</ref> The coenzyme was named coenzyme A to stand for "activation of acetate". In 1953, [[Fritz Lipmann]] won the Nobel Prize in Physiology or Medicine "for his discovery of co-enzyme A and its importance for intermediary metabolism".<ref name=":0" /><ref>{{cite web|title=Fritz Lipmann – Facts |website=Nobelprize.org |publisher=Nobel Media AB |date=2014 |access-date=8 November 2017 |url=http://www.nobelprize.org/nobel_prizes/medicine/laureates/1953/lipmann-facts.html}}</ref>

==Biosynthesis==

Coenzyme A is naturally synthesized from [[Pantothenic acid|pantothenate]] (vitamin B₅), which is found in food such as meat, vegetables, cereal grains, legumes, eggs, and milk.<ref>{{Cite web|url=http://www.umm.edu/health/medical/altmed/supplement/vitamin-b5-pantothenic-acid|title=Vitamin B₅ (Pantothenic acid)|website=University of Maryland Medical Center|language=en|access-date=2017-11-08|archive-date=2017-10-18|archive-url=https://web.archive.org/web/20171018192121/http://www.umm.edu/health/medical/altmed/supplement/vitamin-b5-pantothenic-acid|url-status=dead}}</ref> In humans and most living organisms, pantothenate is an essential vitamin that has a variety of functions.<ref>{{Cite web|url=https://medlineplus.gov/druginfo/natural/853.html|title=Pantothenic Acid (Vitamin B₅): MedlinePlus Supplements|website=medlineplus.gov|language=en|access-date=2017-12-10|archive-date=2017-12-22|archive-url=https://web.archive.org/web/20171222155558/https://medlineplus.gov/druginfo/natural/853.html|url-status=dead}}</ref>&nbsp;In some plants and bacteria, including ''[[Escherichia coli]]'', pantothenate can be synthesised ''de novo'' and is therefore not considered essential. These bacteria synthesize pantothenate from the amino acid aspartate and a metabolite in valine biosynthesis.<ref name=":3">{{cite journal | vauthors = Leonardi R, Jackowski S | title = Biosynthesis of Pantothenic Acid and Coenzyme A | journal = EcoSal Plus | volume = 2 | issue = 2 | date = April 2007 | pmid = 26443589 | pmc = 4950986 | doi = 10.1128/ecosalplus.3.6.3.4 }}</ref>

In all living organisms, coenzyme A is synthesized in a five-step process that requires four molecules of ATP, pantothenate and cysteine<ref name=":4">{{cite journal | vauthors = Leonardi R, Zhang YM, Rock CO, Jackowski S | title = Coenzyme A: back in action | journal = Progress in Lipid Research | volume = 44 | issue = 2–3 | pages = 125–153 | year = 2005 | pmid = 15893380 | doi = 10.1016/j.plipres.2005.04.001 }}</ref> (see figure):

[[File:CoA_Biosynthetic_Pathway.png|thumb|Details of the biosynthetic pathway of CoA synthesis from pantothenic acid.]]

# [[Pantothenate]] (vitamin B₅) is phosphorylated to 4′-phosphopantothenate by the enzyme [[pantothenate kinase]] (PanK; CoaA; CoaX). This is the committed step in CoA biosynthesis and requires ATP.<ref name=":3" />

# A [[cysteine]] is added to 4′-phosphopantothenate by the enzyme [[phosphopantothenoylcysteine synthetase]] (PPCS; CoaB) to form 4'-phospho-N-pantothenoylcysteine (PPC). This step is coupled with ATP hydrolysis.<ref name=":3" />

# PPC is decarboxylated to [[4'-phosphopantetheine|4′-phosphopantetheine]] by [[phosphopantothenoylcysteine decarboxylase]] (PPC-DC; CoaC)

# 4′-phosphopantetheine is adenylated (or more properly, [[Adenylation|AMPylated]]) to form dephospho-CoA by the enzyme [[Pantetheine-phosphate adenylyltransferase|phosphopantetheine adenylyl transferase]] (COASY; PPAT; CoaD)

# Finally, dephospho-CoA is phosphorylated to coenzyme A by the enzyme [[dephospho-CoA kinase|dephosphocoenzyme A kinase]] (COASY, DPCK; CoaE). This final step requires ATP.<ref name=":3" />

Enzyme nomenclature abbreviations in parentheses represent mammalian, other eukaryotic, and prokaryotic enzymes respectively. In mammals steps 4 and 5 are catalyzed by a bifunctional enzyme called [[COASY]].<ref name="Evers">{{cite journal | vauthors = Evers C, Seitz A, Assmann B, Opladen T, Karch S, Hinderhofer K, Granzow M, Paramasivam N, Eils R, Diessl N, Bartram CR, Moog U | display-authors = 6 | title = Diagnosis of CoPAN by whole exome sequencing: Waking up a sleeping tiger's eye | journal = American Journal of Medical Genetics. Part A | volume = 173 | issue = 7 | pages = 1878–1886 | date = July 2017 | pmid = 28489334 | doi = 10.1002/ajmg.a.38252 | s2cid = 27153945 }}</ref> This pathway is regulated by product inhibition. CoA is a competitive inhibitor for Pantothenate Kinase, which normally binds ATP.<ref name=":3" /> Coenzyme A, three ADP, one monophosphate, and one diphosphate are harvested from biosynthesis.<ref name=":4" />

Coenzyme A can be synthesized through alternate routes when intracellular coenzyme A level are reduced and the ''de novo'' pathway is impaired.<ref>{{cite journal | vauthors = de Villiers M, Strauss E | title = Metabolism: Jump-starting CoA biosynthesis | journal = Nature Chemical Biology | volume = 11 | issue = 10 | pages = 757–758 | date = October 2015 | pmid = 26379022 | doi = 10.1038/nchembio.1912 }}</ref> In these pathways, coenzyme A needs to be provided from an external source, such as food, in order to produce [[4'-phosphopantetheine|4′-phosphopantetheine]]. Ectonucleotide pyrophosphates (ENPP) degrade coenzyme A to 4′-phosphopantetheine, a stable molecule in organisms. [[Acyl carrier protein|Acyl carrier proteins (ACP)]] (such as ACP synthase and ACP degradation) are also used to produce 4′-phosphopantetheine. This pathway allows for 4′-phosphopantetheine to be replenished in the cell and allows for the conversion to coenzyme A through enzymes, PPAT and PPCK.<ref>{{cite journal | vauthors = Sibon OC, Strauss E | title = Coenzyme A: to make it or uptake it? | journal = Nature Reviews. Molecular Cell Biology | volume = 17 | issue = 10 | pages = 605–606 | date = October 2016 | pmid = 27552973 | doi = 10.1038/nrm.2016.110 | s2cid = 10344527 }}</ref>

A 2024 article detailed a plausible chemical synthesis mechanism for the pantetheine component (the main functional part) of coenzyme A in a primordial [[Abiogenesis|prebiotic]] world.

===Commercial production===

Coenzyme A is produced commercially via extraction from yeast, however this is an inefficient process (yields approximately 25&nbsp;mg/kg) resulting in an expensive product. Various ways of producing CoA synthetically, or semi-synthetically have been investigated although none are currently operating at an industrial scale.<ref>{{cite journal | vauthors = Mouterde LM, Stewart JD |title=Isolation and Synthesis of One of the Most Central Cofactors in Metabolism: Coenzyme A |journal=Organic Process Research & Development |volume=23 |pages=19–30 |date=19 December 2018 |doi=10.1021/acs.oprd.8b00348|s2cid=92802641 |url=https://hal.archives-ouvertes.fr/hal-02876007/file/Review%20final%205.0.pdf }}</ref>

== Function ==

=== Fatty acid synthesis ===

Since coenzyme A is, in chemical terms, a [[thiol]], it can react with [[carboxylic acid]]s to form [[thioester]]s, thus functioning as an [[acyl]] group carrier. It assists in transferring [[fatty acid]]s from the [[cytoplasm]] to [[mitochondria]]. A molecule of coenzyme A carrying an [[acyl group]] is also referred to as ''[[acyl-CoA]]''. When it is not attached to an acyl group, it is usually referred to as 'CoASH' or 'HSCoA'. This process facilitates the production of fatty acids in cells, which are essential in cell membrane structure.

Coenzyme A is also the source of the [[phosphopantetheine]] group that is added as a [[prosthetic group]] to proteins such as [[acyl carrier protein]] and [[formyltetrahydrofolate dehydrogenase]].<ref>{{cite journal | vauthors = Elovson J, Vagelos PR | title = Acyl carrier protein. X. Acyl carrier protein synthetase | journal = The Journal of Biological Chemistry | volume = 243 | issue = 13 | pages = 3603–3611 | date = July 1968 | pmid = 4872726 | doi = 10.1016/S0021-9258(19)34183-3 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Strickland KC, Hoeferlin LA, Oleinik NV, Krupenko NI, Krupenko SA | title = Acyl carrier protein-specific 4'-phosphopantetheinyl transferase activates 10-formyltetrahydrofolate dehydrogenase | journal = The Journal of Biological Chemistry | volume = 285 | issue = 3 | pages = 1627–1633 | date = January 2010 | pmid = 19933275 | pmc = 2804320 | doi = 10.1074/jbc.M109.080556 | doi-access = free }}</ref>[[File:CoA_Sources_and_Uses.png|thumb|Some of the sources that CoA comes from and uses in the cell.]]

=== Energy production ===

Coenzyme A is one of five crucial coenzymes that are necessary in the reaction mechanism of the [[citric acid cycle]]. Its acetyl-coenzyme A form is the primary input in the citric acid cycle and is obtained from [[glycolysis]], amino acid metabolism, and fatty acid beta oxidation. This process is the body's primary [[Catabolism|catabolic pathway]] and is essential in breaking down the building blocks of the cell such as [[carbohydrate]]s, [[amino acid]]s, and [[lipid]]s.<ref>{{Cite book | vauthors = Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P |date=2002|title=Molecular Biology of the Cell | edition = 4th | chapter = Chapter 2: How Cells Obtain Energy from Food|publisher=Garland Science | chapter-url=https://www.ncbi.nlm.nih.gov/books/NBK26882/|language=en}}</ref>

=== Regulation ===

When there is excess glucose, coenzyme A is used in the cytosol for synthesis of fatty acids.<ref name=":2">{{cite journal | vauthors = Shi L, Tu BP | title = Acetyl-CoA and the regulation of metabolism: mechanisms and consequences | journal = Current Opinion in Cell Biology | volume = 33 | pages = 125–131 | date = April 2015 | pmid = 25703630 | pmc = 4380630 | doi = 10.1016/j.ceb.2015.02.003 }}</ref> This process is implemented by regulation of [[acetyl-CoA carboxylase]], which catalyzes the committed step in fatty acid synthesis. [[Insulin]] stimulates acetyl-CoA carboxylase, while [[epinephrine]] and [[glucagon]] inhibit its activity.<ref>{{Cite book | vauthors = Berg JM, Tymoczko JL, Stryer L |date=2002 | title = Biochemistry | chapter = Acetyl Coenzyme A Carboxylase Plays a Key Role in Controlling Fatty Acid Metabolism| chapter-url=https://www.ncbi.nlm.nih.gov/books/NBK22381/|language=en}}</ref>

During cell starvation, coenzyme A is synthesized and transports fatty acids in the cytosol to the mitochondria. Here, acetyl-CoA is generated for oxidation and energy production.<ref name=":2" /> In the citric acid cycle, coenzyme A works as an allosteric regulator in the stimulation of the enzyme [[pyruvate dehydrogenase]].

=== Antioxidant function and regulation ===

Discovery of the novel antioxidant function of coenzyme A highlights its protective role during cellular stress. Mammalian and Bacterial cells subjected to oxidative and metabolic stress show significant increase in the covalent modification of protein cysteine residues by coenzyme A.<ref>{{cite journal | vauthors = Tsuchiya Y, Peak-Chew SY, Newell C, Miller-Aidoo S, Mangal S, Zhyvoloup A, Bakovic J, Malanchuk O, Pereira GC, Kotiadis V, Szabadkai G, Duchen MR, Campbell M, Cuenca SR, Vidal-Puig A, James AM, Murphy MP, Filonenko V, Skehel M, Gout I | display-authors = 6 | title = Protein CoAlation: a redox-regulated protein modification by coenzyme A in mammalian cells | journal = The Biochemical Journal | volume = 474 | issue = 14 | pages = 2489–2508 | date = July 2017 | pmid = 28341808 | pmc = 5509381 | doi = 10.1042/BCJ20170129 }}</ref><ref name="Tsuchiya 1909–1937">{{cite journal | vauthors = Tsuchiya Y, Zhyvoloup A, Baković J, Thomas N, Yu BY, Das S, Orengo C, Newell C, Ward J, Saladino G, Comitani F, Gervasio FL, Malanchuk OM, Khoruzhenko AI, Filonenko V, Peak-Chew SY, Skehel M, Gout I | display-authors = 6 | title = Protein CoAlation and antioxidant function of coenzyme A in prokaryotic cells | journal = The Biochemical Journal | volume = 475 | issue = 11 | pages = 1909–1937 | date = June 2018 | pmid = 29626155 | pmc = 5989533 | doi = 10.1042/BCJ20180043 }}</ref> This reversible modification is termed protein CoAlation (Protein-S-SCoA), which plays a similar role to [[S-Glutathionylation|protein ''S''-glutathionylation]] by preventing the irreversible oxidation of the [[Thiol|thiol group]] of cysteine residues.

Using anti-coenzyme A antibody<ref>{{Cite journal | vauthors = Malanchuk OM, Panasyuk GG, Serbyn NM, Gout IT, Filonenko VV |date=2015 |title=Generation and characterization of monoclonal antibodies specific to Coenzyme A |url=http://biopolymers.org.ua/content/31/3/187/ |journal=Biopolymers and Cell |language=EN |volume=31 |issue=3 |pages=187–192 |doi=10.7124/bc.0008DF |issn=0233-7657|doi-access=free }}</ref> and liquid chromatography tandem mass spectrometry ([[Liquid chromatography–mass spectrometry|LC-MS/MS]]) methodologies, more than 2,000 CoAlated proteins were identified from stressed mammalian and bacterial cells.<ref name=":1">{{cite journal | vauthors = Tossounian MA, Baczynska M, Dalton W, Newell C, Ma Y, Das S, Semelak JA, Estrin DA, Filonenko V, Trujillo M, Peak-Chew SY, Skehel M, Fraternali F, Orengo C, Gout I | display-authors = 6 | title = Profiling the Site of Protein CoAlation and Coenzyme A Stabilization Interactions | journal = Antioxidants | volume = 11 | issue = 7 | pages = 1362 | date = July 2022 | pmid = 35883853 | pmc = 9312308 | doi = 10.3390/antiox11071362 | doi-access = free }}</ref> The majority of these proteins are involved in cellular metabolism and stress response.<ref name=":1" /> Different research studies have focused on deciphering the coenzyme A-mediated regulation of proteins. Upon protein CoAlation, inhibition of the catalytic activity of different proteins (e.g. metastasis suppressor [[NME1]], [[PRDX5|peroxiredoxin 5]], [[Glyceraldehyde 3-phosphate dehydrogenase|GAPDH]], among others) is reported.<ref>{{cite journal | vauthors = Tossounian MA, Zhang B, Gout I | title = The Writers, Readers, and Erasers in Redox Regulation of GAPDH | journal = Antioxidants | volume = 9 | issue = 12 | pages = 1288 | date = December 2020 | pmid = 33339386 | pmc = 7765867 | doi = 10.3390/antiox9121288 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Yu BY, Tossounian MA, Hristov SD, Lawrence R, Arora P, Tsuchiya Y, Peak-Chew SY, Filonenko V, Oxenford S, Angell R, Gouge J, Skehel M, Gout I | display-authors = 6 | title = Regulation of metastasis suppressor NME1 by a key metabolic cofactor coenzyme A | journal = Redox Biology | volume = 44 | pages = 101978 | date = August 2021 | pmid = 33903070 | pmc = 8212152 | doi = 10.1016/j.redox.2021.101978 }}</ref><ref name="Tsuchiya 1909–1937"/><ref>{{cite journal | vauthors = Baković J, Yu BY, Silva D, Chew SP, Kim S, Ahn SH, Palmer L, Aloum L, Stanzani G, Malanchuk O, Duchen MR, Singer M, Filonenko V, Lee TH, Skehel M, Gout I | display-authors = 6 | title = A key metabolic integrator, coenzyme A, modulates the activity of peroxiredoxin 5 via covalent modification | journal = Molecular and Cellular Biochemistry | volume = 461 | issue = 1–2 | pages = 91–102 | date = November 2019 | pmid = 31375973 | pmc = 6790197 | doi = 10.1007/s11010-019-03593-w }}</ref> To restore the protein's activity, antioxidant enzymes that reduce the disulfide bond between coenzyme A and the protein cysteine residue play an important role. This process is termed protein deCoAlation. So far, two bacterial proteins, Thioredoxin A and Thioredoxin-like protein (YtpP), are shown to deCoAlate proteins.<ref>{{cite journal | vauthors = Tossounian MA, Baczynska M, Dalton W, Peak-Chew SY, Undzenas K, Korza G, Filonenko V, Skehel M, Setlow P, Gout I | display-authors = 6 | title = ''Bacillus subtilis'' YtpP and Thioredoxin A Are New Players in the Coenzyme-A-Mediated Defense Mechanism against Cellular Stress | journal = Antioxidants | volume = 12 | issue = 4 | pages = 938 | date = April 2023 | pmid = 37107313 | pmc = 10136147 | doi = 10.3390/antiox12040938 | doi-access = free }}</ref>

==Use in biological research==

Coenzyme A is available from various chemical suppliers as the free acid and [[lithium]] or [[sodium]] salts. The free acid of coenzyme A is detectably unstable, with around 5% degradation observed after 6 months when stored at −20&nbsp;°C,<ref name="Dawson_2002" /> and near complete degradation after 1 month at 37&nbsp;°C.<ref>{{cite web|title=Datasheet for free acid coenzyme A|url=http://www.oycus.com/wp-content/uploads/2014/08/Co-A.pdf|publisher=Oriental Yeast Co., LTD.}}</ref> The lithium and sodium salts of CoA are more stable, with negligible degradation noted over several months at various temperatures.<ref>{{cite web|title=Datasheet for lithium salt coenzyme A|url=http://www.oycus.com/wp-content/uploads/2014/08/Co-A-Li.pdf|publisher=Oriental Yeast Co., LTD.}}</ref> Aqueous solutions of coenzyme A are unstable above pH&nbsp;8, with 31% of activity lost after 24 hours at 25&nbsp;°C and pH&nbsp;8. CoA stock solutions are relatively stable when frozen at pH&nbsp;2–6. The major route of CoA activity loss is likely the air oxidation of CoA to CoA disulfides. CoA mixed disulfides, such as CoA-''S''–''S''-glutathione, are commonly noted contaminants in commercial preparations of CoA.<ref name="Dawson_2002" /> Free CoA can be regenerated from CoA disulfide and mixed CoA disulfides with reducing agents such as [[dithiothreitol]] or [[2-mercaptoethanol]].

==Non-exhaustive list of coenzyme A-activated acyl groups==

{{Category see also|Thioesters of coenzyme A}}

*[[Acetyl-CoA]]

*[[fatty acyl-CoA]] (activated form of all fatty acids; only the CoA esters are substrates for important reactions such as mono-, di-, and triacylglycerol synthesis, [[carnitine palmitoyl transferase]], and [[cholesterol]] [[esterification]])

**[[Propionyl-CoA]]

**[[Butyryl-CoA]]

**Myristoyl-CoA

**[[Crotonyl-CoA]]

*[[Acetoacetyl-CoA]]

*[[Coumaroyl-Coenzyme A|Coumaroyl-CoA]] (used in [[flavonoid]] and [[stilbenoid]] biosynthesis)

*[[Benzoyl-CoA]]

*[[Phenylacetyl-CoA]]

* Acyl derived from [[dicarboxylic acid]]s

**[[Malonyl-CoA]] (important in chain elongation in [[fatty acid biosynthesis]] and [[polyketide]] biosynthesis)

**[[Succinyl-CoA]] (used in [[heme]] biosynthesis)

**[[Hydroxymethylglutaryl-CoA]] (used in [[isoprenoid]] biosynthesis)

**[[pimelate|Pimelyl-CoA]] (used in [[biotin]] biosynthesis)

== References ==

{{reflist}}

==Bibliography==

* {{cite book |title=Lehninger: Principles of Biochemistry |edition=4th | vauthors = Nelson DL, Cox MM |location=New York |year=2005 |publisher=W .H. Freeman |isbn=978-0-7167-4339-2 |url-access=registration |url=https://archive.org/details/lehningerprincip00lehn_0 }}

{{Commons category|Coenzyme A}}

{{Enzyme cofactors}}

[[Category:Coenzymes]]

[[Category:Metabolism]]

[[Category:Thiols]]