IV. THE CHEMICAL PROCESSES IN PLANT 

 RESPIRATION 



I. THE ANAEROBIC MATERIAL TRANSFORMATIONS AND THE 

 PARTICIPATING ENZYMES 



By virtue of the preceding exposition it is advisable to con- 

 sider the material transformations of respiration from the 

 standpoint of the theory of the genetic connection of anaerobic 

 with normal respiration. Consequently we assume that the 

 handhng of matter in normal respiration may be divided into 

 two groups of reactions — anaerobic cleavage processes and 

 oxidative processes. We wish now to deal with the cleavage 

 processes. 



It has already been emphasized that ethyl alcohol is formed 

 regularly by the anaerobic respiration of plants. Kostychev 

 failed to observe a formation of alcohol only in the case of the 

 following: i. fruiting bodies oi Psalliota campestris, 2. dormant 

 potato tubers, 3. peptone cultures of Aspergillus niger. Of 

 course all these objects produced considerable quantities of 

 CO2 in the absence of oxygen. It was certainly important to 

 determine whether enzymes of alcohoHc fermentation appear 

 in aerobic plants. This question may also be answered in the 

 affirmative. Shortly after the discovery of zymase in yeast 

 Stoklasa^ exhibited preparations from seed-plants which fer- 

 mented sugar to ethyl alcohol and COo. At first this gave rise 

 to doubt whether bacteria were not to be regarded as the cause 

 of the fermentation. Later zymase was isolated by Kostychev- 

 from pure cultures of various aerobic molds. Palladin and 

 Kostychev^ also established beyond question the action of 

 zymase in various killed seed-plants through the exclusion of 



1 Stoklasa, J. und Cerny. Ber. d. chem. Ges. 36: 622. 1903; Zentralbl. f. Physiol. 16: 

 652. 1903: Stoklasa, Jelinek, and Vitek. Hofm. Beitr. 3: 460. 1903; Stoklasa, Cerny, 

 Jelinek, and Vitek. Zentralbl. f. Bakt., Parasitenk, u. Infektionskrankh. (II). 13 : 86. 1904; 

 Stoklasa. Zentralbl. f. Physiol. 17: 465- 1903; Arch. ges. Physiol. loi : 311. 1904. 



2 Kostytschew, S. Ber. d. bot. Ges. 22: 207. 1904; Zentralbl. f. Bakt., Parasitenk. u. 

 Infektionskrankh. (II). 13: 490. 1904. 



3 Palladin, W. und S. Kostytschew. Z. f. physiol. Chem. 48: 214. 1906. 



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