185 



The niicleoproteidH might, llierefore, be ranked with acids in 

 general, both on account of their acid-qualities and on account of 

 their coagulating qualities, if not Pkkelkaring were of opinion tiiat 

 the nucleoproteids, together with calcium, produce a ferment, which 

 ferment would have to be looked upon as the cause of blood- 

 coagulation, while likewise most other investigators attribute the 

 coagulation of blood to a fibrin-ferment. 



Since, however, it has appeared from my investigations that the 

 relation between fibrinogen and fibrin is of such an extremely 

 simple kind, it seems strange that the transition of the foi'mer sub- 

 stance into the latter, which process is in fact nothing but a with- 

 drawal of ions of OH from fibrinogen, should require a ferment- 

 action. Tlie more so since, as we observed before, the action of the 

 nucleoproteids might be readily explained by the acidity of these 

 substances. 



The conception that the nucleoproteids owe their coagulating 

 properties to their acidity, would at once explain why nucleoproteids 

 of such different origin, and also nucleohistons and nucleoalbumens 

 all have the power of effecting coagulation, the reason being that 

 all these substances act as acids. 



Judging myself entitled on the ground of the investigation, of 

 which a short summary has been given in the preceding pages, to 

 the conclusion : 



That fibrinogen, as found in the blood, must be looked upon as 

 an alkali-adsorption compound of fibrin, in other ivords, as fibrin 

 lüliich, under the influence of adsorbed urns of OH, is in a finely 

 divided and swollen state, iji a sol state; that consequenthj the transi- 

 tion of fibrinogen into fibrin, that is to say the coagulation of blood, 

 must be based upon a withdrawal of ions of OH from, fibrinogen, 

 I think 1 may add the supposition that the natural blood-coagula- 

 tion must be the result of the withdrawal of ions of OH from 

 fibrinogen by nucleoproteids in consequence of their acidity. 



H' this supposition is found to be correct, further investigations 

 will have to teach if nucleoproteids act as such, or if their coagu- 

 lating capacity is due to the formation of niicleinic acid or phos- 

 phoric acid, and also what part is possibly played by calcium in 

 this process. Moreover it will have to be explained how this acid- 

 action of the nucleoproteids can have impressed various investigators 

 as being a ferment-action. 



Groningen, April 1913. Physiological Laboratory. 



