ANTI-ENZYME IMMUNITY 241 



minutes, no measurable amount of acetylhexosamine could be detected 

 for 50 minutes; the maximum liberation was not attained until con- 

 siderably after two hr. had elapsed. When the concentrations of the 

 enzymes from different sources were adjusted so that their reaction 

 times for the reduction of viscosity were similar, it was found that 

 the amounts of enzyme necessary to liberate measurable quantities 

 of reducing substance were approximately the same whatever the 

 source of the enzyme. The time lag in the liberation of reducing sub- 

 stances, coupled with the lack of complete correlation between this 

 activity and the reduction of viscosity, suggested that two separate 

 mechanisms may be involved; if the enzymes are not identical, they 

 must be closely associated, since they were not separated by any existing 

 method of purification and were similarly influenced by variations in 

 the environment of the reaction. 



4. Distribution and Physiological Significance of Hya- 

 luronidase or the Permeability Factor 



All the investigators confirmed the original observation of Duran- 

 Reynals that testicular extracts contain this enzyme or the permeability 

 factor. It is likewise found in leech head extracts (Claude, 1937, 1940; 

 Favilli, 1940) and in certain snake venoms (Duran-Reynals, 1939; 

 Favilli, 1940, etc.). The findings of Duran-Reynals in this regard are 

 as follows: The factor is most abundant in the venom of the Vi'peridae 

 (rattlesnake) family and relatively scant in the venom of the Colu- 

 hridae 'proteroglypha (cobra) family, and it is absent from toad venom. 

 Extracts of the supralabial glands of harmless snakes contain only 

 negligible amounts of the factor. It is present in various normal tissues 

 (Duran-Reynals, 1928) and in rapidly growing grafted mammalian 

 tumors (Boyland and McClean, 1935). 



a. Relation of Hyaluronidase Production to Virulence of Bac- 

 teria. The presence and absence of this factor in numerous bacteria 

 has been reported. Some of these reports are confirmatory and certain 

 others contradictory. The discrepancy among the findings of various 

 investigators may be due to differences of strains used, method of grow- 

 ing and the age of the culture, methods of testing the activity of the 

 preparations, and methods of preparation of enzymes. Such differences 

 of enzyme activities among various strains of a given type or species 



