THE FORMATION OF PROTEIDS IN PLANT-CELLS. 



63 



C 4 H 8 N 2 0 3 + C 6 H l2 O e + 20 = 2C + H 7 N0 2 + 2C0 2 + 3HX>. 



Asparagin. Aspartic aldehyde. 



The condensation process, however, leading from this 

 highly labil I) — and still hypothetical — amido-aldehyde to the 

 active albumen must be accompanied by a reducing process and 

 by the entrance of sulfur. We may express this process by 

 the following equations : 



3 C 4 H 7 N0 2 = C l2 H^O.+^ITO; 



Aspartic aldehyde Intermediate product 



6C 12 H 17 N 3 0, + 12H + H 2 S = C 72 H II2 N l 8 S0 2 , +2H 2 O. 



Licbcrki'ihn' s albumin-formula. 



For the reduction indicated in the latter equation the 

 presence of glucose would be again required. 2 ' If we now make 

 the assumption that under certain chemical conditions the 

 aldehyde groups are prevented from acting during the condensa- 

 tion process upon the amido-groups (which is to be expected 

 under normal conditions) and that the hydrogen serving for 

 reduction would transform 12 aldehyde groups into secondary 

 alcoholic groups (CHOH), causing thereby a pinakon-like link- 

 ing — then we should have in the final product — the active 

 albumen — a substance of extraordinary lability, containing 12 

 aldehyde- and 18 amido-groups in one molecule, and changing 

 easily into another product with the loss of its aldehydic 

 character — the passive albumen. 



The accumulation of asparagin is evidently connected with 

 the gradual disappearance of the amido-products, directly result- 

 ing from a decomposition of protein. This fact finds its most 

 natural explanation if we recall the conclusions, to which we 

 were led by the study of the nourishment of the lower fungi (see 

 page 49). We had logically concluded that if different com- 

 pounds serve to yield the same protein, then they must be trans- 

 formed first into one and the same atomic group from which the 

 protein formation can start. We had seen that this group cannot 



1) Amido-aldehydes are as we have explained in Chapt. Ill exceedingly unstable 

 compounds, which may play important physiological roles in more than one respect. 

 Wolffemtein observed recently an easy transformation of amido-valeraldehyde into 

 piperidin, and holds it highly probable that amido-aldehydes form the connecting 

 links between the fatty series and the alkaloids in plants. 



2) On glucose as a reducing agent in neutral or even acid solutions, see Chapt. VI . 



