MATERIAL TRANSFORMATIONS IN THE PLANT 



159 



The decomposition of formative proteins (nucleo-proteins and nucleo- 

 albumins) may be estimated from the decrease in phosphorus-containing pro- 

 teins. Ivanov' determined the amounts of phosphorus of various kinds of 

 compounds, in seeds and etiolated seedlings of Vicia faba, and obtained the 

 results given in the table below, where the numbers are percentages, on the basis 

 of total phosphorus content. 



Seeds 



Seedlings 

 5 Days Old 



Seedlings 

 20 Days Old 



Phosphorus of inorganic phosphates 



Phosphorus of lecithin 



Phosphorus of proteins 



Phosphorus of organic phosphates . . 



II. 4 

 II. 6 

 S2-S 

 25 -7 



48.1 



37-4 

 9.8 



80.2 



6.6 



13-7 



Germination in darkness thus appears to be correlated with a pronounced 

 decomposition of phosphorus-containing proteins. In resting seeds protein 

 phosphorus amounted to 52.5 per cent, of the total phosphorus content, while 

 seedlings twenty days old contained protein phosphorus amounting to only 

 13.7 per cent.; in the latter case most of the phosphorus occurred as inorganic 

 phosphates.^ Zaliesskii^ obtained results similar to these. He found, for ex- 

 ample, that the phosphorus-containing proteins disappear from the cotyledons of 

 germinating seeds, while the amount of these proteins increases markedly in 

 the axial organs, since growth is accompanied by synthetic processes. Thus, 

 in the axial parts of Vicia faba seedlings three days old, the ratio of protein phos- 

 phorus to protein nitrogen was found to be 0.0125 10.0850 (i :6.8), while the 

 corresponding ratio for seedlings nine days old was 0.0337 = 0-3755 (^ • n-i)- 



The researches of Butkevich, Zaliesskii,* Ivanpv,^ Kovshov^ and Gromow' 

 show that the cleavage of phophorus- containing as well as that of phosphorus- 

 free proteins is dependent upon enzymatic processes. 



1 Iwanow, Leonid, Ueber die tJmwandlungen des Phosphors beim Keimen der Wicke. (Vorlaufige 

 Mittheilung.) Ber. Deutsch. Bot. Ges. 20: 366-372. 1902. Idem, Ueber die Umwandlungen des Phos- 

 phors in der Pflanze im Zusammenhange mit der Eiweissstoffmetamorphose. Arbeit. Naturforscherges. 

 St. Petersburg 34: 1-170. 1905. [Russian.] [Rev. in: Bot. Centralbl. 103 : 83. 1906.] 



2 Vorbrodt, Wlad., Untersuchungen uber die Phosphorverbindungen in den Pflanzensamen, mit be- 

 sonderer Berucksichtigung des Phytins. [Title also in Russian. Text in German.] Bull, internat. 

 (classe sd. math, et nat., ser A.) Acad. Sci. Cracovie 1910: 414-511. 1910. 



' Zaleski, W., Beitrage zur Verwandlung des Eiweissphosphors in den Pflanzen. Ber. Deutsch. Bot. 

 Ges. 20: 426-433. 1902. Idem, Ueber den Umsatz der Nucleinsaure in keimenden Samen. Ibid. 

 25: 349-356. 1907. 



' Zaleski, W., Beitrage zur Kenntnis der Eiweissbildung in reifenden Samen. (Vorlaufige Mitteilung.) 

 Ber. Deutsch. Bot. Ges. 23 : 126-133. 1905. Idem, Zur Kenntnis der proteolytischen Enzyme der rei- 

 fenden Samen. Ibid. 23: 133-142. 1905. Idem, Ueber den Umsatz der Phosphorverbindungen in 

 reifenden Samen. Ibid. 23 : 58-66. 1907. Idem, Ueber die autolytische Ammoniakbildung in den Pflan- 

 zen. Ibid. 25 : 357-360. 1907. Idem, 1907. [See note 3, this page.] 



6 Ivanov, 1902, 1905. [See note i, this page.] 



" KoTShov, I. D., Fermentative Eisweisszersetzung in erfrorenen Pflanzen. [Russian, with German 

 abstract.] Trav. Soo. Imp. Nat. St.-P6tersbourg 33" (Jour. bot. i) : 180-185. 1906. [German abstract, 

 p. 187.] 



' Gromow, T., and Grigoriew, C, Die Arbeit der Zymase and der Endotryptase in den abgetoteten 

 Hefezellen unter veischiedenen Verhaltnissen. Zeitsch. physiol. Chem. 42 : 299-329. 1904. 



