410 



N. M. SISAKYAN 



have been found. The conditions under which the protein was hydrolysed arouse 

 a suspicion that the spots which were found on the chromatogram may have 

 been the spots of peptides which resisted hydrolysis [63]. 



When studying the chromatographic amino acid composition of phycoerythrin 

 from Callithamnion rybosiim we only found 17 amino acids common to the 

 proteins of higher plants [70]. Tryptophan was not found. Small quantities 

 of a- and y-aminobutyric acids were formed, we suppose, from threonine and 

 glutamic acid respectively during hydrolysis. Our findings were confirmed by 

 Fujiwara for phycoerythrin from Porphyra tenera [65], Analysis of the curves 

 presented by Fujiwara shows that, in his experiments too, there were traces 

 of a- and y-aminobutyric acids. 



Unlike the qualitative amino acid composition of the proteins of the photo- 

 synthesizing organs, their quantitative amino acid composition is not similar in 

 different classes of plants, as may be seen from Table 5. 



Table 5 



Amino acid composition of the proteins of photosynthesizing organs 



(N of amino acids as % of N of protein) 



This is understandable when we remember that the quantitative amino acid 

 composition of the protein of even a single organism varies with differences in 



