{{chembox | Verifiedfields = changed | Watchedfields = changed | verifiedrevid = 433271578 | ImageFileL1 = Mycothiol structure.png | ImageSizeL1 = 125px | ImageFileR1 = Mycothiol ball and stick.png | ImageSizeR1 = 125px | ImageFile2 = Mycothiol spacefill.png | ImageSize2 = 150px |IUPACName=(2''R'')-2-acetamido-''N''-[(2''R'',3''R'',4''R'',5''S'',6''R'')-4,5-dihydroxy-6-(hydroxymethyl)-2-[(2''R'',3''S'',5''R'',6''R'')-2,3,4,5,6-pentahydroxycyclohexyl]oxyoxan-3-yl]-3-sulfanylpropanamide |OtherNames=Mycothiol |Section1={{Chembox Identifiers | CASNo_Ref = {{cascite|correct|??}} | CASNo=192126-76-4 | PubChem=441148 | ChEBI_Ref = {{ebicite|changed|EBI}} | ChEBI = 16768 | ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}} | ChemSpiderID = 10193006 | SMILES = CC(=O)N[C@@H](CS)C(=O)N[C@@H]1[C@H]([C@@H]([C@H](O[C@@H]1O[C@@H]2[C@@H]([C@@H]([C@H]([C@@H]([C@H]2O)O)O)O)O)CO)O)O | InChI = 1/C17H30N2O12S/c1-4(21)18-5(3-32)16(29)19-7-9(23)8(22)6(2-20)30-17(7)31-15-13(27)11(25)10(24)12(26)14(15)28/h5-15,17,20,22-28,32H,2-3H2,1H3,(H,18,21)(H,19,29)/t5-,6+,7+,8+,9+,10-,11-,12+,13+,14+,15-,17+/m0/s1 | InChIKey = MQBCDKMPXVYCGO-FQBKTPCVBG | StdInChI_Ref = {{stdinchicite|changed|chemspider}} | StdInChI = 1S/C17H30N2O12S/c1-4(21)18-5(3-32)16(29)19-7-9(23)8(22)6(2-20)30-17(7)31-15-13(27)11(25)10(24)12(26)14(15)28/h5-15,17,20,22-28,32H,2-3H2,1H3,(H,18,21)(H,19,29)/t5-,6+,7+,8+,9+,10-,11-,12+,13+,14+,15-,17+/m0/s1 | StdInChIKey_Ref = {{stdinchicite|changed|chemspider}} | StdInChIKey = MQBCDKMPXVYCGO-FQBKTPCVSA-N | RTECS = | MeSHName = | KEGG_Ref = {{keggcite|changed|kegg}} | KEGG = C06717 }} |Section2={{Chembox Properties | C = 17 | H = 30 | N = 2 | O = 12 | S = 1 }} }}

'''Mycothiol''' (MSH or AcCys-GlcN-Ins) is an unusual thiol compound found in the Actinomycetota.<ref>{{cite journal |author=Fahey RC |title=Novel thiols of prokaryotes |journal=Annu. Rev. Microbiol. |volume=55 |pages=333–56 |year=2001 |pmid=11544359 |doi=10.1146/annurev.micro.55.1.333}}</ref><ref>Jothivasan VK, Hamilton CJ, (2008) Mycothiol: synthesis, biosynthesis and biological functions of the major low molecular weight thiol in actinomycetes. Natural Product Reports, (25). 1091-1117 [https://dx.doi.org/10.1039/b616489g]</ref> It is composed of a cysteine residue with an acetylated amino group linked to glucosamine, which is then linked to inositol.<ref>{{cite journal |vauthors=Newton GL, Buchmeier N, Fahey RC |title=Biosynthesis and functions of mycothiol, the unique protective thiol of Actinobacteria |journal=Microbiol. Mol. Biol. Rev. |volume=72 |issue=3 |pages=471–94 |date=September 2008 |pmid=18772286 |doi=10.1128/MMBR.00008-08 |pmc=2546866}}</ref> The oxidized, disulfide form of mycothiol (MSSM) is called mycothione, and is reduced to mycothiol by the flavoprotein mycothione reductase.<ref>{{cite journal |vauthors=Patel MP, Blanchard JS |title=Expression, purification, and characterization of Mycobacterium tuberculosis mycothione reductase |journal=Biochemistry |volume=38 |issue=36 |pages=11827–33 |date=September 1999 |pmid=10512639 |doi=10.1021/bi991025h}}</ref><ref>{{cite journal |vauthors=Patel MP, Blanchard JS |title=Mycobacterium tuberculosis mycothione reductase: pH dependence of the kinetic parameters and kinetic isotope effects |journal=Biochemistry |volume=40 |issue=17 |pages=5119–26 |date=May 2001 |pmid=11318633 |doi=10.1021/bi0029144}}</ref> Mycothiol biosynthesis and mycothiol-dependent enzymes such as mycothiol-dependent formaldehyde dehydrogenase and mycothione reductase have been proposed to be good drug targets for the development of treatments for tuberculosis.<ref>{{cite journal |vauthors=Rawat M, Av-Gay Y |title=Mycothiol-dependent proteins in actinomycetes |journal=FEMS Microbiol. Rev. |volume=31 |issue=3 |pages=278–92 |date=April 2007 |pmid=17286835 |doi=10.1111/j.1574-6976.2006.00062.x|doi-access=free }}</ref><ref>{{cite journal |vauthors=Newton GL, Fahey RC |title=Mycothiol biochemistry |journal=Arch. Microbiol. |volume=178 |issue=6 |pages=388–94 |date=December 2002 |pmid=12420157 |doi=10.1007/s00203-002-0469-4|bibcode=2002ArMic.178..388N |s2cid=23893254 }}</ref>

== See also == * Glutathione, analogous function in other bacteria * Bacillithiol

== References == {{reflist}}

== External links == *[https://archive.today/20121224172559/http://web.uct.ac.za/depts/chempath/pathogens.htm The Biochemistry of Pathogens: The metabolism and function of mycothiol in the mycobacteria.]

Category:Thiols Category:Acetamides Category:Propionamides Category:Tetrahydropyrans