ALBUMINS OR PROTEINS. 155 



We can assume that cadaverine is formed by splitting off carbon dioxide 

 from lysine, which has the empirical formula C 6 H 14 N 2 O 2 : 



CH 2 . CH 2 . CH 2 . CH 2 . CH . COOH 



NH 2 NH 2 



Lysine 



= CH 2 . CH 2 . CH 2 . CH 2 . CH 2 + CO 2 



NH 2 NH 2 



Cadaverine 



By synthesizing the inactive lysine, Emil Fischer and Fritz Weigert 1 have 

 shown that lysine is, as the above formula indicates, an a-, e-, diamino- 

 caproic acid. 



E. Schulze 2 has also found lysine in germinating plants. It is widely 

 distributed among the proteins and is rarely absent from them. It reacts 

 strongly alkaline. As yet it has not been obtained in crystalline form. 

 It rotates polarized light towards the right. 



Arginine was discovered by E. Schulze and Steiger s in the cotyledons of 

 lupine seeds, and in the etiols of germinating pumpkin seeds. It rotates 

 towards the right, and likewise reacts alkaline. It was soon shown that 

 arginine could not be considered an individual compound in the same sense 

 as the other amino acids mentioned. E. Schulze and E. Winterstein 4 

 then showed that arginine yields urea and a base, on treatment with baryta 

 water. Schulze and Winterstein isolated this base by forming its benzoyl 

 derivative. This had the same composition and properties as a di-benzoyl 

 compound isolated by Jaffe 5 from the excreta of hens, which had been 

 fed benzoic acid. It proved to be a benzoyl compound of ornithine, 

 and was called by Jaffe, omithuric acid. Jaffe recognized ornithine as 

 diaminovaleric acid. Ellinger 6 corroborated this view in the same manner 

 as was done with lysine, by acting on ornithine with putrefactive bacteria 

 and obtaining tetramethylenediamine (putrescine) . By this conversion 

 it was shown that the two amino groups occupy the a and d positions. 

 The splitting of ornithine occurs in the following manner: 



CH 2 . CH 2 . CH 2 . CH . COOH = CH 2 . CH 2 . CH 2 . CH 2 + CO 2 

 NH 2 NH 2 NH 2 NH 2 



1 E. Fischer andF. Weigert: Sitzber. Akad. Wiss. Berlin, 1902; Ber. 36, 3772 (1902). 



2 E. Schulze: Z. physiol. Chem. 24, 18 (1898); 30, 276 (1900); 28, 465 (1899). 



3 E. Schulze and E. Steiger: ibid. 11, 43 (1887); Ber. 30, 2879 (1898). 



4 E. Schulze and E. Winterstein : Z. physiol. Chem. 26, 1 (1898) ; Ber. 30, 2879 (1898). 

 * M. Jaffe: ibid. 10, 1925 (1877); 11, 401 (1878). 



a A. Ellinger: loc. dt. 



