BY JAMES M. PETRI E. 829 



the experimental evidence of Suzuki(94) ? which shows that, by 

 addition of ammonium salts to the seedling, the amount of 

 asparagin was greatly increased. When the etiolated plants were 

 grown in a space free from oxygen, there was no increase; while 

 those plants grown in oxygen showed a large increase. He then 

 concludes that oxidation-processes play a part in germination. 

 Schulze has, in fact, found oxidation-products. During develop- 

 ment, the organic sulphur from the decomposing proteins is 

 oxidised to sulphate, and the latter increases with development. 

 A second c*se was discovered by Bertel(95), who showed in 

 Lupinus luteus the fate of tyrosin, how by an enzyme it is 

 oxidised to homogentisic acid, and, finally, by oxidation the ring 

 is completely destroyed. This change includes the addition of 

 (OH) groups, and the casting out of (NH 2 ), the latter being 

 equivalent to the formation of ammonia. Then by asphyxiating 

 the seedlings with chloroform, i.e., preventing oxidation, Bertel 

 caused the tyrosin to accumulate in large quantities. A number 

 of peroxidases have been discovered, together with the peroxides 

 upon which they act. 



Castoro(92) examined seedlings at various stages for ammonia, 

 and found that, even after several weeks growing in the dark 

 the maximum was only 0-13 % of the dry material. It is very 

 significant, therefore, that the ammonia does not accumulate in 

 the living seedling, and that the amount present is only very 

 small. Schulze's important conclusion(96) is that, in the meta- 

 bolism, the ammonia is used up, and that, most probably, it is 

 used in the synthetic formation of amides. These amides are, 

 therefore, secondary products, and owe their origin to the primary 

 compounds. He adds, further, that it is also possible for a 

 limited quantity of amides to originate direct from the cleavage 

 of protein, as it is well known that aspartic and glutaminic acids 

 are always obtained by acid- or alkali-hydrolysis; and, by careful 

 enzyme-hydrolysis, the amides may be obtained direct. 



These are the views of Schulze, as proved by his experiments 

 on the metabolism of seedlings, supported by the work of Balicka- 

 Iwanowska(97) in 1903, and Prianischnikow(98) in 1904. The 

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