PHYSICAL AND CHEMICAL PROPERTIES OF SNAKE VENOM 81 



clear filtrate, and if the boiling was too prolonged the peptone broke down and 

 gave fine coagula. The following reactions were obtained with this fraction : 



TABLE 4. 



No immediate coagulation at a tempera- Mercuric chloride, decided precipitate. 



ture of 100 C. Absolute alcohol, precipitate, redissolved by the 



Full reactions with the protein color tests. addition of water. 



No precipitate with weak or strong nitric Mercuric nitrate, decided precipitate. 



acid. Pot. hydrate, precipitated by saturation. 



Ferric chloride, no precipitate. Pot. ferrpcyanide in presence of weak acetic acid, 



Cupric sulphate, no precipitate. a precipitate. 



Moccasin peptone resembles the above (crotalus) closely. On the other 

 hand, Mitchell and Reichert met some remarkable properties of a similar 

 preparation obtained from cobra venom. It was not precipitated by mercuric 

 chloride or absolute alcohol. In watery solution all venom peptones pro- 

 duced fine coagula when boiled for a few minutes. After filtration, the filtrate 

 again gave similar fine coagula on boiling, and so the process of boiling, 

 filtering, and reboiling the filtrate went on repeatedly, yet a clear filtrate 

 could not be obtained even after one hour's repetition. Mitchell and Reichert 

 considered this peculiarity to be a decomposition phenomenon of a protein as 

 a result of violent physical force. 



The cobra peptone reacted positively to the xantho-proteic, Millon and 

 biuret. There was no precipitate by strong nitric, hydrochloric, or acetic 

 acids, but precipitation resulted by saturated sodic chloride, tannic acid, and 

 basic-lead acetate. 



Reverting to the identity of the fractions of coagulable proteins obtained 

 from the different venoms by the same methods, Mitchell and Reichert give 

 comparative lists of their solubility and heat-coagulability. Salt-free sus- 

 pension of the water-venom globulins of Crotalus terrificus and Cobra, and the 

 copper-venom globulin and dialysis-venom globulin of Crotalus terrificus are 

 recorded as coagulable by heat, while no coagulation or even clearing up is 

 observed by them with the three globulin fractions of Ancistrodon piscivorus. 



Except that the water- venom globulin of this latter snake is insoluble in 

 acetic acid (5 per cent or glacial), no remarkable differences are noticeable, 

 and again three fractions behave alike to a certain extent. 



Mitchell and Reichert give the following composition of the venom proteins 

 in two crotaline and one elapine snakes: 



TABLE 5. 

 Crotalus adamanteus: 



0.5 gm. dried venom water-venom globulin 0.0495 g m - 



copper- venom globulin 0.0375 S" 1 - 

 dialysis-venom globulin 0.0360 gm. 



0.1230 gm.= globulins. 

 0.3770 gm.=peptone (estimated). 

 Ancistrodon piscivorus: 



0.3364 gm. dried venom water-venom globulin 0.0034 gm. 

 copper-venom globulin 0.0182 gm. 

 dialysis-venom globulin 0.0047 g m - 



0.0263 gm. = globulins 

 0.3101 gm. =peptone (estimated). 

 Cobra: 



o.a gm. dried venom water globulin 0.0035 



peptone 0.1965 (estimated). 



