Trypanothione

C27H49N9O10S2 (reduced) 723.86 g/mol (reduced) Trypanothione is an unusual form of glutathione containing two molecules of glutathione joined by a spermidine (polyamine) linker. It is found in parasitic protozoa such as leishmania and trypanosomes. These protozoal parasites are the cause of leishmaniasis, sleeping sickness and Chagas' disease. Trypanothione was discovered by Alan Fairlamb. Its structure was proven by chemical synthesis.{{Cite journal

Trypanothione-dependent enzymes include reductases, peroxidases, glyoxalases and transferases. Trypanothione-disulfide reductase (TryR) was the first trypanothione-dependent enzyme to be discovered (EC 1.8.1.12). It is an NADPH-dependent flavoenzyme that reduces trypanothione disulfide. TryR is essential for survival of these parasites both in vitro and in the human host.

A major function of trypanothione is in the defence against oxidative stress. Here, trypanothione-dependent enzymes such as tryparedoxin peroxidase (TryP) reduce peroxides using electrons donated either directly from trypanothione, or via the redox intermediate tryparedoxin (TryX). Trypanothione-dependent hydrogen peroxide metabolism is particularly important in these organisms because they lack catalase. Since the trypanosomatids also lack an equivalent of thioredoxin reductase, trypanothione reductase is the sole path that electrons can take from NADPH to these antioxidant enzymes.