224 LIFE: ITS NATURE AND ORIGIN 



edge is sufficient to permit us to refer a disease or symptoms of an 

 ailment to abnormal catalyst conditions. 



To illustrate how extensive may be the varieties of chemical 

 and enzymic attack on an organism following infection by a single 

 agent, Dr. John E. Blair, of the Hospital for Joint Diseases, kindly 

 prepared for me an outline regarding the toxins and enzymes or 

 enzyme-like substances (catalysts) generally liberated by Staphylo- 

 cocci, the common cause of boils, carbuncles and similar troubles. 

 The following is based on this outline. 



Toxins and other products of Staphylococci 



Toxins 



(1) Exotoxin. This soluble, filtrable, thermolabile product can 

 produce demonecrosis, hemolysis, and death, and may be a mixture 

 of "lethal toxin," necrotoxin, and hemolysins, mentioned below. 11 



(2) Necrotoxin. Produces intense necrosis on intradermal injection, 

 liberating leucotaxine which initiates blocking off of the infected 

 area. 12 



(3) Lethal Toxin. Venous injection quickly kills mice and rabbits. 

 Mice killed in 2 to 4 minutes by 0.05 ml. 13 



(4) Enterotoxin. Soluble, filterable, thermostable; responsible for 

 food poisoning due to staphylococci. 14 



(5) Leucocidin. Destructive for leucocytes, often causing their com- 

 plete disintegration. Produced in varying amounts by most path- 

 ogenic staphylococci, especially those responsible for furuncles and 

 severe infections. 15 



Enzymes 



(1) Alpha-hemolysin. 0.002 ml often hemolyses 1 per cent rabbit 

 erythrocytes in 1 hour at 37° C. Little or no action on human red 

 cells and apparently not harmful to humans, though produced by 

 many Staphylococci harmful to man. Useful in estimating the 

 potency of exotoxin, whose titer it closely parallels. 16 



(2) Beta-hemolysin. Hydrolyzes sheep and human cells, but not 

 rabbit cells. Found in animal, and occasionally in human strains. 

 No apparent relation to pathogenicity. 17 



(3) Gamma-hemolysin. Affects rabbit cells; no evident pathogen- 

 icity. 18 



(4) Spreading Factor. Increases permeability of connective tissue, 

 until negatived by leucotaxine action. 19 



(5) Coagulase. Induces clotting of glood plasma and fibrinogen 

 solutions. Found only in pathogenic staphylococci, and useful in 

 their laboratory identification. 20 



