576 simion oeriu 



Table 3 



Mean content of oxidized, reduced and ordinary glutathione in the blood of old rats 

 treated with methionine or cysteine (50 mg/kg of body weight daily for 16 days) 



Oxidized Reduced Ordinary 



glutathione glutathione glutathione 



(mg/ioo ml blood) 



UNTREATED ANIMALS 



765 288 365 



(-1-5; +0-45) (-0-2; rO-i) (-0-3; +0-9) 



ANIMALS TREATED WITH METHIONINE 



711 283 35-5 



(-0-99; +0-86) (-2-32; +3-09) ( -2-34; +0-5) 



ANIMALS TREATED WITH CYSTEINE 



5 -88 34 -2 40-1 



(-1-69; +I-5I) (-0-8; -fo-8) (-0-87J +073) 



Note: The figures in brackets show the deviation of the maximal and minimal values 

 from the mean. 



In animals which are not treated with methionine or cysteine the content of 

 oxidized glutathione increases with age. 



The administration of methionine to old animals leads to an insignificant 

 decrease in the content of oxidized glutathione (from 7-65 to 7-11 mg/ioo ml); 

 the administration of cysteine leads to a considerable decrease in the content 

 of oxidized glutathione (from 7-65 to 5-88 mg/ioo ml). 



In another series of experiments we aimed at studying the possibility of the 

 transformation of cysteine into methionine in the plant organism Aspergillus 

 niger. 



The literature shows that this organism does not contain methionine. 



Following the principle of the unity of the organism with the conditions of 

 its existence, we changed the conditions of hfe of the mould by adding different 

 amounts of cysteine and methionine to the nutrient medium. 



We added methionine (0-5% and 2%) or cysteine (1%) to Kaufman's syn- 

 thetic medium*, on which we cultivated Aspergillus niger, for 23 days. 



Chromatographic determination of the amino acid composition of the 

 Aspergillus niger gave the following results. "f" Methionine was absent from 

 hydrolysates of the fungus grown on the basal medium, but present when 

 methionine or cysteine had been added. 



* We used Kaufman's synthetic medium: maltose 5 g, magnesium sulphate 01 g, 

 calcium nitrate 05 g, potassium acid phosphate 025 g, distilled water to 1000 ml. 



t Wc used the method of partition chromatography. Whatman No. i filter paper was 

 used. A mixture of butanol, glacial acetic acid and water was used as the solvent. The 

 solution was made to flow for 32 hours in one direction at room temperature (20-22 "^C). 

 The chromatogram was developed with a 02 "„ solution of ninhydrin in butanol and then 

 dried for 10 min at no C. 



