174 PAPAIN-PROTEOLYSIS. 



that the products which result from the action of papayotin 

 upon albuminous substances are identical with those formed 

 by the action of superheated water. This implies that the so- 

 called atmid products and the papayotin products are alike in 

 their resistance to the action of pepsin,* for it is assumed at 

 least that it is the presence of this enzyme in the kidney which 

 leads to the hydration of the ordinary albumoses during their 

 elimination from the body. In the case of rabbits, where 

 pepsin is wanting in the kidney, the injection of albumoses 

 into the blood is followed by their elimination unchanged 

 (Neumeister). 



Moreover, there are certain peculiarities in the chemical 

 composition of the atmid bodies,! shared to some degree by the 

 proteoses formed by the action of bromelin J the proteolytic 

 enzyme of pineapple juice which lends favor to the view 

 that these bodies are not quite identical with the proteoses, 

 etc., formed by animal enzymes. Consequently, it seemed 

 desirable to study with some care the physiological behavior of 

 the albumoses and peptone resulting from papain-digestion 

 with a view to ascertaining what differences of a physiological 

 nature, if any, exist between the latter products and those 

 resulting from animal enzymes. 



As has already been pointed out, the soluble products which 

 are formed in the digestion of coagulated egg-albumin with 

 papain are mainly deuteroalbumose and peptone. These were 

 prepared in considerable quantity by digesting the coagulated 

 albumin from four dozen hen's eggs with 9 grams of papain 

 in 2 liters of 0.25 per cent sodium carbonate for 48 hours at 



* Since this paper was written, there has appeared an article by E. Sal- 

 kowski, "Ueber die Einwirkung des iiberhitzten Wassers auf Eiweiss," 

 Zeitschr. f. Biol., 1897, xxxiv, p. 190 (Jubelband zu Ehren von W. Kiihne), in 

 which it is stated that the atmidalbumose formed by him from blood-fibrin 

 was not resistant to the action of either pepsin, trypsin, or bacteria, thus 

 differing widely from Neumeister's product. 



t Chittenden and Meara, A Study of the Primary Products Resulting 

 from the Action of Superheated Water on Coagulated Egg-albumin. Journal 

 of Physiology, 1894, xv, p. 601. 



{ Chittenden, The Proteolytic Action of Bromelin, the Ferment of Pine- 

 apple Juice. Ibid., 1894, xv, p. 249. 



