THE FORMATION OF PROTEIDS IN PLANT-CELLS. 
6l 
however, an erroneous assumption, for experiments with bacteria 
and with mould-fungi have convinced us that asparagin and 
aspartic acid form most excellent nutrients, being evidently very 
favorable sources of carbon and nitrogen for the formation of 
protein, for the growth of protoplasm, i. e. multiplication of 
cells. These combinations are far superior to tyrosin or phenyl- 
amidopropionic acid, which would, moreover, have to undergo a 
thorough chemical change before the formation of proteids 
could commence. 
An observation of E. Schulze is, in this connection, of fun¬ 
damental importance. He found that the quantity of amido- 
acids formed during the first period of germination is con¬ 
tinually decreasing , whilst the amount of asparagin is increasing ; 
he showed furthermore, that the proportion of asparagin is much 
greater in the axial organs than in the cotyledons, as is seen 
from the following table : 
The protein-free 
extract contains 
nitrogen in form of : 
Lupin shoots. 
In the cotyledons. 
In the axial parts. 
Asparagin. 
Other amido- 
compounds. 
Asparagin. 
Other amido- 
compounds. 
6 days old. 
. 20,5 
79,5 
68,8 
3 L 2 
12 days old. 
26,2 
73.8 
78,1 
21,1 
ioo parts of lupin-shoots containing 16,8 parts of asparagin 
yielded, after 3 weeks vegetation in diffused daylight, 151 parts 
of green plants with 23,9 parts of asparagin. 1 ) The primary 
amido-products disappear first, their carbon serves partially to 
support respiration, while another part of their carbon together 
with their nitrogen is found now in form of asparagin, and this 
again disappears finally with the increase of available glucose, 
formed by the function of the chlorophyll. The asparagin 
evidently indicates the manner of the protein formation, it is 
1) Landw. Jahrb. 9, 41. The sulfur of the decomposed protein is converted into 
sulfates, which later serve afterwards again in reconstruction of the proteids 
(E. Schulze ; Tamann). 
