EXPERIMENTS WITH BACTERIAL ENZYMES * 



Edwin O. Jordan. 



Introductory. 



Technique. 



Conditions of Gelatinase Formation. 



Composition of Medium. 



Reaction of Medium. 

 Physical Characters. 



Resistance of Gelatinase to Heat. 



Filtration. 

 Conditions of Activity. 



Reaction of Medium. 



Temperature. 

 The Action of Formalin upon Liquefied Gelatin. 



The Relation Between Bacterial Gelatinases and Bacterial Hemolysins. 

 Summary and Conclusions. 



INTRODUCTORY. 



It was first shown in 1886 by Bitter' that the liquefaction of gelatin 

 by bacteria depends upon enzyme action. Rietsch,^ Senger,^ 

 Jerosch/ Sternberg, ^ Krabbe,^ and others confirmed and somewhat 

 extended Bitter's observations, and in 1890-92 Fermi^ published 

 comprehensive investigations upon the properties of gelatin-liquefying 

 and other bacterial enzymes. 



The power of bacterial filtrates to liquefy gelatin is a more or less 

 independent quality. It is true that various experimenters have not 

 distinguished between the gelatin-liquefying ferments and other "pro- 

 teolytic" enzymes, and have openly or tacitly assumed that gelatino- 

 lytic ability is a measure of general proteolytic power. Malfitano,* 

 however, has shown that the albuminolytic and gelatinolytic proper- 

 ties of anthrax filtrates are really distinct and should not be con- 

 founded. This writer states that it is possible to weaken or even 

 destroy the albuminolytic power of an anthrax filtrate without 



* Received for publication January 3, igo6. 



' Arch. j. Hyg., 1886, 5, p. 245. * Baumgarten's Jahrb., 1887, 3, p. 104. 



• Jour, de pharm. et de chimie, 1887, 16, p. 8. ' Ibid, p. 363. 



* Baumgarten's Jahrb., 1887, 3, p. 104. * Jahrb. wiss. Bot., 1890, 21, p. 32°- 

 ' Centralbl. /. Bakl., 1890, 7, p. 469; ibid., 1891, 10, p. 401; ibid., 1892, 12, p. 713. 



• Compt. rend, de la Soc. de Biol., 1903, 55, p. 843. 



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