Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 1997 Aug 1;325(Pt 3):623–629. doi: 10.1042/bj3250623

Biosynthesis of mycothiol: elucidation of the sequence of steps in Mycobacterium smegmatis.

C Bornemann 1, M A Jardine 1, H S Spies 1, D J Steenkamp 1
PMCID: PMC1218604  PMID: 9271081

Abstract

Several members of the Actinomycetales, including the medically important mycobacteria, produce 1-D-myo-inosityl-2-(N-acetyl-L-cysteinyl)amino-2-deoxy-alpha-D- glucop yranoside (trivial name mycothiol) as their principal low-molecular-mass thiol. The pseudo-disaccharide component of mycothiol, 1-D-myo-inosityl-2-amino-2-deoxy-alpha-D-glucopyranoside (alpha-D-GI), was synthesized by ligation of 1-D,L-2,3,4,5, 6-penta-O-acetyl-myo-inositol to 3,4,6-tri-O-acetyl-2-deoxy- 2-(2,4-dinitrophenylamino)-alpha-D-glu- copyranosyl bromide to give, in the first instance, an isomeric mixture of alpha- and beta-linked pseudo-disaccharides. The alpha-coupled D,D and D,L isomers, alpha-D-GI and alpha-L-GI respectively, were purified from the mixture by TLC, followed by removal of the protecting groups. A cell-free extract of Mycobacterium smegmatis catalysed the ligation of cysteine, acetate and alpha-D-GI in the presence of ATP and Mg2+ to form mycothiol, as judged by HPLC. When no acetate was added to the incubation mixture, an additional thiol accumulated. In the presence of [14C]acetate no radiolabel was recovered in this species, but only in mycothiol. The additional thiol was isolated as the bimane derivative, and 1H and 1H-1H COSY NMR spectra confirmed its identity as desacetylmycothiol. A more complete conversion of desacetylmycothiol into mycothiol was achieved in the presence of acetyl-S-CoA. These results indicate that the biosynthesis of mycothiol proceeds by the sequential addition of cysteine and acetate to alpha-D-GI. The inositol moiety appears to be an important determinant of specificity, since alpha-L-GI was poorly utilized.

Full Text

The Full Text of this article is available as a PDF (854.2 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Christman M. F., Morgan R. W., Jacobson F. S., Ames B. N. Positive control of a regulon for defenses against oxidative stress and some heat-shock proteins in Salmonella typhimurium. Cell. 1985 Jul;41(3):753–762. doi: 10.1016/s0092-8674(85)80056-8. [DOI] [PubMed] [Google Scholar]
  2. Claesson R., Edlund M. B., Persson S., Carlsson J. Production of volatile sulfur compounds by various Fusobacterium species. Oral Microbiol Immunol. 1990 Jun;5(3):137–142. doi: 10.1111/j.1399-302x.1990.tb00411.x. [DOI] [PubMed] [Google Scholar]
  3. Doering T. L., Masterson W. J., Englund P. T., Hart G. W. Biosynthesis of the glycosyl phosphatidylinositol membrane anchor of the trypanosome variant surface glycoprotein. Origin of the non-acetylated glucosamine. J Biol Chem. 1989 Jul 5;264(19):11168–11173. [PubMed] [Google Scholar]
  4. Duncan K., Walsh C. T. ATP-dependent inactivation and slow binding inhibition of Salmonella typhimurium D-alanine:D-alanine ligase (ADP) by (aminoalkyl)phosphinate and aminophosphonate analogues of D-alanine. Biochemistry. 1988 May 17;27(10):3709–3714. doi: 10.1021/bi00410a028. [DOI] [PubMed] [Google Scholar]
  5. Fahey R. C. Biologically important thiol-disulfide reactions and the role of cyst(e)ine in proteins: an evolutionary perspective. Adv Exp Med Biol. 1977;86A:1–30. doi: 10.1007/978-1-4684-3282-4_1. [DOI] [PubMed] [Google Scholar]
  6. Fahey R. C., Brown W. C., Adams W. B., Worsham M. B. Occurrence of glutathione in bacteria. J Bacteriol. 1978 Mar;133(3):1126–1129. doi: 10.1128/jb.133.3.1126-1129.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Fahey R. C., Sundquist A. R. Evolution of glutathione metabolism. Adv Enzymol Relat Areas Mol Biol. 1991;64:1–53. doi: 10.1002/9780470123102.ch1. [DOI] [PubMed] [Google Scholar]
  8. Garbe T. R., Hibler N. S., Deretic V. Response of Mycobacterium tuberculosis to reactive oxygen and nitrogen intermediates. Mol Med. 1996 Jan;2(1):134–142. [PMC free article] [PubMed] [Google Scholar]
  9. Grassetti D. R., Murray J. F., Jr Determination of sulfhydryl groups with 2,2'- or 4,4'-dithiodipyridine. Arch Biochem Biophys. 1967 Mar;119(1):41–49. doi: 10.1016/0003-9861(67)90426-2. [DOI] [PubMed] [Google Scholar]
  10. JONES M. E., BLACK S., FLYNN R. M., LIPMANN F. Acetyl coenzyme a synthesis through pyrophosphoryl split of adenosine triphosphate. Biochim Biophys Acta. 1953 Sep-Oct;12(1-2):141–149. doi: 10.1016/0006-3002(53)90133-4. [DOI] [PubMed] [Google Scholar]
  11. Krauth-Siegel R. L., Schöneck R. Flavoprotein structure and mechanism. 5. Trypanothione reductase and lipoamide dehydrogenase as targets for a structure-based drug design. FASEB J. 1995 Sep;9(12):1138–1146. doi: 10.1096/fasebj.9.12.7672506. [DOI] [PubMed] [Google Scholar]
  12. Newton G. L., Bewley C. A., Dwyer T. J., Horn R., Aharonowitz Y., Cohen G., Davies J., Faulkner D. J., Fahey R. C. The structure of U17 isolated from Streptomyces clavuligerus and its properties as an antioxidant thiol. Eur J Biochem. 1995 Jun 1;230(2):821–825. doi: 10.1111/j.1432-1033.1995.0821h.x. [DOI] [PubMed] [Google Scholar]
  13. Penninckx M. J., Elskens M. T. Metabolism and functions of glutathione in micro-organisms. Adv Microb Physiol. 1993;34:239–301. doi: 10.1016/s0065-2911(08)60031-4. [DOI] [PubMed] [Google Scholar]
  14. Sakuda S., Zhou Z. Y., Yamada Y. Structure of a novel disulfide of 2-(N-acetylcysteinyl)amido-2-deoxy-alpha-D-glucopyranosyl-myo-inositol produced by Streptomyces sp. Biosci Biotechnol Biochem. 1994 Jul;58(7):1347–1348. doi: 10.1271/bbb.58.1347. [DOI] [PubMed] [Google Scholar]
  15. Sherman D. R., Mdluli K., Hickey M. J., Arain T. M., Morris S. L., Barry C. E., 3rd, Stover C. K. Compensatory ahpC gene expression in isoniazid-resistant Mycobacterium tuberculosis. Science. 1996 Jun 14;272(5268):1641–1643. doi: 10.1126/science.272.5268.1641. [DOI] [PubMed] [Google Scholar]
  16. Sherman D. R., Sabo P. J., Hickey M. J., Arain T. M., Mahairas G. G., Yuan Y., Barry C. E., 3rd, Stover C. K. Disparate responses to oxidative stress in saprophytic and pathogenic mycobacteria. Proc Natl Acad Sci U S A. 1995 Jul 3;92(14):6625–6629. doi: 10.1073/pnas.92.14.6625. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Soda K. Microbial sulfur amino acids: an overview. Methods Enzymol. 1987;143:453–459. doi: 10.1016/0076-6879(87)43080-2. [DOI] [PubMed] [Google Scholar]
  18. Spies H. S., Steenkamp D. J. Thiols of intracellular pathogens. Identification of ovothiol A in Leishmania donovani and structural analysis of a novel thiol from Mycobacterium bovis. Eur J Biochem. 1994 Aug 15;224(1):203–213. doi: 10.1111/j.1432-1033.1994.tb20013.x. [DOI] [PubMed] [Google Scholar]
  19. Steenkamp D. J., Spies H. S. Identification of a major low-molecular-mass thiol of the trypanosomatid Crithidia fasciculata as ovothiol A. Facile isolation and structural analysis of the bimane derivative. Eur J Biochem. 1994 Jul 1;223(1):43–50. doi: 10.1111/j.1432-1033.1994.tb18964.x. [DOI] [PubMed] [Google Scholar]
  20. Storz G., Tartaglia L. A. OxyR: a regulator of antioxidant genes. J Nutr. 1992 Mar;122(3 Suppl):627–630. doi: 10.1093/jn/122.suppl_3.627. [DOI] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES