AbstractsBiology & Animal Science

In 1888, de Rey Pailhade for the first time described a substance containing sulfur which he had been able to isolate from yeast in an impure state and he called this substance "Philothion". Hopkins in 1921, iso1ated from yeast cells a low molecular weight sulfur containing substance which he named "glutathione". Finding that the compound gave a positive nitroprusside reaction and contained glutamic acid and cysteine he concluded that it probably was a dipeptide of these amino acids. Eight years later Hunter and Eagles questioned the validity of the dipeptide structure and Hopkins was prompted to reinvestigate the constitution of the compound. With the aid of cuprous oxide as a reagent he was able to isolate glutathione as a copper derivative and from it to isolate glutathione itself in a crystalline form. On further analysis he found the substance to be a tripeptide consisting of glutamic acid, cysteine and glycine. Soon afterward Pirie and Pinhey performed for the first time the electrometric titration of the ionizable groups in glutathione and proposed the correct structure of the compound. This finding was confirmed by degradation studies and by the synthesis of the compound by Harington and Mead. [...]