Mycothiol Explained

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]}

See also

• Glutathione, analogous function in other Bacteria
• Bacillithiol

References

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

External links

• The Biochemistry of Pathogens: The metabolism and function of mycothiol in the mycobacteria.

Notes and References

1. Fahey RC . Novel thiols of prokaryotes . Annu. Rev. Microbiol. . 55 . 333–56 . 2001 . 11544359 . 10.1146/annurev.micro.55.1.333.
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 https://dx.doi.org/10.1039/b616489g
3. Newton GL, Buchmeier N, Fahey RC . Biosynthesis and functions of mycothiol, the unique protective thiol of Actinobacteria . Microbiol. Mol. Biol. Rev. . 72 . 3 . 471–94 . September 2008 . 18772286 . 10.1128/MMBR.00008-08 . 2546866.
4. Patel MP, Blanchard JS . Expression, purification, and characterization of Mycobacterium tuberculosis mycothione reductase . Biochemistry . 38 . 36 . 11827–33 . September 1999 . 10512639 . 10.1021/bi991025h.
5. Patel MP, Blanchard JS . Mycobacterium tuberculosis mycothione reductase: pH dependence of the kinetic parameters and kinetic isotope effects . Biochemistry . 40 . 17 . 5119–26 . May 2001 . 11318633 . 10.1021/bi0029144.
6. Rawat M, Av-Gay Y . Mycothiol-dependent proteins in actinomycetes . FEMS Microbiol. Rev. . 31 . 3 . 278–92 . April 2007 . 17286835 . 10.1111/j.1574-6976.2006.00062.x. free .
7. Newton GL, Fahey RC . Mycothiol biochemistry . Arch. Microbiol. . 178 . 6 . 388–94 . December 2002 . 12420157 . 10.1007/s00203-002-0469-4. 23893254 .