METHYL GUANIDIN. 283 



from impure cultures on beef-broth of Finkler and Prior's vibrio 

 proteus, containing ordinary putrefaction bacteria, for twenty to 

 thirty days at 37°— 38°. Vibrio proteus alone seems incapable of 

 forming this base. The comma bacillus, after some time (six weeks), 

 partially decomposes creatinin with formation of a small quantity of 

 methyl guanidin (Brieger). The bacillus of anthrax likewise is cap- 

 able of transforming creatin into methyl guanidin. It has been 

 found in rabbits that died of rabbit septicemia. 



It occurs in the mercuric chlorid filtrate (Brieger), from which it 

 is obtained, after the removal of the mercury by hydrogen sulphid, 

 on precipitation with phosphomolybdic acid. The precipitate is de- 

 composed with neutral lead acetate, and the filtrate from this, after 

 removal of the lead by hydrogen sulphid, is concentrated and then 

 sodium picrate added. The resinous picrate precipitate is purified by 

 boiling with much water, and, finally, it is recrystallized from boil- 

 ing absolute alcohol. According to Bocklisch, it occurs in the mer- 

 curic chlorid precipitate (not in the filtrate), from which it is isolated, 

 after removal of the mercury and concentration of the clear filtrate, 

 by precipitation with sodium picrate. The precipitate, containing 

 cadaverin, methyl guanidin, and creatinin, is boiled with absolute 

 alcohol (cadaverin picrate is insoluble) and the alcoholic solution is 

 then evaporated to drive off the alcohol and taken up with water. 

 From this aqueous solution, after removal of picric acid, methyl 

 guanidin is precipitated by gold chlorid whereas creatinin remains 

 in solution. 



This ptomain is identical with the synthetic methyl guanidin 

 (methyluramin), which can be readUy obtained by boiling a creatin 

 solution with mercuric oxid or with lead dioxid and dilute sul- 

 phuric acid (Dessaignes). The parent substance of methyl guan- 

 idin as it occurs in putrefaction is undoubtedly the creatin which 

 exists preformed in the muscular tissue. If such is the ease, the 

 bacteria engaged in its production must be considered as possessing 

 an oxidizing action, since this base is prepared synthetically from 

 creatin by oxidation. The change would correspond to that observed 

 in the putrefaction of ornithin and lysin whereby putrescin and ca- 

 daverin result (p. 268). The methyl guanidin in turn may be con- 

 verted into methyl urea and this into ammonia and methylamin. 

 That creatin does not offer much resistance to the action of bacteria 

 is shown in the fact that Friedlander's pneumococcus, which 

 possesses but small chemical powers, is capable of slowly but stead- 

 ily decomposing creatin, yielding as one of the products acetic acid. 

 Strecker and Erlenmeyer, as well as Baumann, have shown that 

 creatin, although a substituted guanidin, is not poisonous, but is 

 readily converted into creatinin which is a relatively toxic sub- 

 stance. On the other hand, guanidin and methyl guanidin are quite 

 violent poisons. This is, therefore, another instance in which a toxic 



