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. 1989 Apr;86(8):2607–2611. doi: 10.1073/pnas.86.8.2607

Trypanothione is the primary target for arsenical drugs against African trypanosomes.

A H Fairlamb 1, G B Henderson 1, A Cerami 1
PMCID: PMC286966  PMID: 2704738

Abstract

The trypanosomatid metabolite N1,N8-bis-(glutathionyl)spermidine (trypanothione) has been demonstrated to form a stable adduct with the aromatic arsenical drug melarsen oxide [p-(4,6-diamino-s-triazinyl-2-yl)aminophenyl arsenoxide]. The stability constant of the melarsen-trypanothione adduct (Mel T) has been determined to be 1.05 x 10(7) M-1. When bloodstream Trypanosoma brucei are incubated with either melarsen oxide or the 2,3-dimercaptopropanol adduct of melarsen oxide (melarsoprol), Mel T is the only arsenical derivative detectable in acid-soluble extracts of the cells. Trypanothione may therefore be regarded as a primary target for aromatic arsenical derivatives against African trypanosomes. The selective toxic action of these compounds might arise through sequestration of intracellular trypanothione in the form of Mel T, or Mel T itself may be toxic within the cell. The latter possibility is illustrated by the finding that Mel T is an inhibitor of trypanothione reductase from T. brucei (Ki = 9.0 microM)--an enzyme that is central to the regulation of the thiol/disulfide redox balance in the parasite and absent from the host.

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Selected References

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

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