ASPARAGINE 59 



developing parts* in greater abundance than in the members 

 where the reserve proteins are stored ; Schulze f found that only 

 7*62 per cent of asparagine occurred in the cotyledons, whilst 

 3 1 -8 1 per cent obtained in the axis of the lupin. Also the 

 relative amounts of asparagine and aspartic acid show consider- 

 able variation during germination and, in the last stages, the 

 amount of asparagine formed is in a proportion greater than the 

 amount of protein decomposed. In the instance of Cicer 

 arietinum, there is a marked increase in the amount of amino 

 acids and their amides during germination, which increase is at 

 the expense of the proteins. J Similarly there is an accumula- 

 tion of amides in the shoots of germinating peas ; the amount 

 of amide nitrogen in the seed leaves fluctuates much at first but 

 in the later stages of germination there is a marked increase, 

 whilst, concurrently, the a-amino acids decrease in amount and 

 and finally disappear. From these and such like facts there 

 is no doubt that in the plant asparagine, and possibly also 

 other amides, have their origin in the dissociation of the already 

 elaborated protein. 



With regard to the formation of asparagine, this compound 

 may possibly be produced by the combination of ammonia and 

 aspartic acid || to form ammonium aspartate which gives origin 

 to the asparagine by the loss of a molecule of water. Prianich- 

 nikov,*F whilst recognizing in ammonia the end product of 

 protein dissociation, considers that it also is an initial stage in the 

 formation of proteins and, according to him, asparagine is the 

 form in which it is stored. 



Sure and Tottingham, from the relationship obtaining 

 between the amides and amino acids during the germination 

 of the pea, consider that the amino acids serve for the produc- 

 tion of amides in the plant. 



Asparagine lends itself to condensation more or less readily, 



* This may easily be shown by germinating lupin seeds in the dark until the 

 hypocotyl is a few inches in length. On mounting a section of the hypocotyl in 

 strong alcohol and examining under the microscope, a large number of crystals 

 of asparagine will be seen. 



t Schulze : " Landw. Jahrb.," 1878, 411. 



JZlataroff : " Biochem. Zeitsch.," 1916, 75, 200. 



Sure and Tottingham : " Journ. Biol. Chem.," 1916, 26, 535. 



|| Schulze: loc. cit. Prianichnikov : " Ber. deut. bot. Gesells.," 1904, 22, 

 35. Treboux: " Ber. deut. bot. Gesells.," 1904, 22, 570. 



II Prianichnikov ; " Bull. Agric. Intell.," 1917, , 204, 



