Mycothiol

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Mycothiol
Mycothiol structure.png
Mycothiol ball and stick.png
Mycothiol spacefill.png
Names
IUPAC name
(2R)-2-acetamido-N-[(2R,3R,4R,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-[(2R,3S,5R,6R)-2,3,4,5,6-pentahydroxycyclohexyl]oxyoxan-3-yl]-3-sulfanylpropanamide
Other names
Mycothiol
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
KEGG
PubChem CID
  • InChI=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 X mark.svgN
    Key: MQBCDKMPXVYCGO-FQBKTPCVSA-N X mark.svgN
  • 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
    Key: MQBCDKMPXVYCGO-FQBKTPCVBG
  • 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
Properties
C17H30N2O12S
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).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Mycothiol (MSH or AcCys-GlcN-Ins) is an unusual thiol compound found in the Actinomycetota. [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]

Contents

See also

Related Research Articles

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L-cysteine:1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside ligase is an enzyme with systematic name L-cysteine:1-O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol ligase (AMP-forming). This enzyme catalyses the following chemical reaction

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References

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  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
  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. S2CID   23893254.

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