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Mycothiol (MSH or AcCys-GlcN-Ins) is an unusual thiol compound found in the Actinobacteria.[1][2] It is composed of a cysteine residue with an acetylated amino group linked to glucosamine, which is then linked to inositol.[3] The oxidized, disulfide form of mycothiol (MSSM) is called mycothione, and is reduced to mycothiol by the flavoprotein mycothione reductase.[4][5] 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.[6][7]

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IUPAC name
Other names
3D model (JSmol)
Molar mass 486.49 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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  1. ^ Fahey RC (2001). "Novel thiols of prokaryotes". Annu. Rev. Microbiol. 55: 333–56. doi:10.1146/annurev.micro.55.1.333. PMID 11544359.
  2. ^ 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 [1]
  3. ^ Newton GL, Buchmeier N, Fahey RC (September 2008). "Biosynthesis and functions of mycothiol, the unique protective thiol of Actinobacteria". Microbiol. Mol. Biol. Rev. 72 (3): 471–94. doi:10.1128/MMBR.00008-08. PMC 2546866. PMID 18772286.
  4. ^ Patel MP, Blanchard JS (September 1999). "Expression, purification, and characterization of Mycobacterium tuberculosis mycothione reductase". Biochemistry. 38 (36): 11827–33. doi:10.1021/bi991025h. PMID 10512639.
  5. ^ Patel MP, Blanchard JS (May 2001). "Mycobacterium tuberculosis mycothione reductase: pH dependence of the kinetic parameters and kinetic isotope effects". Biochemistry. 40 (17): 5119–26. doi:10.1021/bi0029144. PMID 11318633.
  6. ^ Rawat M, Av-Gay Y (April 2007). "Mycothiol-dependent proteins in actinomycetes". FEMS Microbiol. Rev. 31 (3): 278–92. doi:10.1111/j.1574-6976.2006.00062.x. PMID 17286835.
  7. ^ Newton GL, Fahey RC (December 2002). "Mycothiol biochemistry". Arch. Microbiol. 178 (6): 388–94. doi:10.1007/s00203-002-0469-4. PMID 12420157.

Mycobacterium tuberculosis is extraordinarily sensitive to killing by a vitamin C-induced Fenton reaction Published 21 May 2013. Nature Communications4, Article number:1881 doi:10.1038/ncomms2898

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