50 BACTERIA AND SOIL FERTILITY 



temperature. Increase of temperature up to a certain point 

 means an increase in their activities. Above this they decrease, 

 and if the tempertaure becomes too high the enzyme is destroyed. 

 Like animals, they are destroyed by poisons. During the life of 

 the bacteria these enzymes are working in harmony, each perform- 

 ing its allotted task — some building up this part of their home, 

 the cell, others preparing the fuel, and still others doing ^w^y 

 Vi^ith vi^aste products. Just the minute life ceases, each enzyme 

 commences to work independent of all others, and in time their 

 home, the cell, is torn to pieces. This is likened unto a dance. 

 As long as the music continues all are in step and there is a cer- 

 tain beautiful rhythm in all. When the music ceases, however, 

 the dancers lose step, bump into each other, and if they continue 

 all becomes confusion. The enzymes are the dancers in the liv- 

 ing cell; life is the master musician who furnishes the music. 

 Hence, enzymes manifest themselves in the living and are sub- 

 ject to the limitations of life in a degree, but they are not life. 



Pigments. — ^AU have heard of the miracle of the bleeding 

 host. The consecrated bread left over night in the moist bacterial 

 laden air of the chapel appears on the morrow besprinkled with 

 bright red drops. What could it be? Blood! From whence did 

 it come and what did it indicate? Various were the interpreta- 

 tions placed upon it, and numerous the lives and homes which 

 were sacrified through this delusion. 



The mystery, romance, and tragedy disappears when one sees 

 a tiny organism. Bacillus frodigiosus^ in the laboratory growing in 

 tubes of starchy food and producing a blood-red pigment. Some- 

 times today bread becomes infected with this organism, and dough 

 which has been set aside over night has been found in the morning 

 to fairly rival in color that of the autumn sunset. 



At times milk on standing develops a very uncanny blue color, 

 which spreads through the dairy like an epidemic. The little 

 culprit which has played this trick is the Bacillus fyocyaneus. 



In the soil are nitrogen-fixing bacteria which form a golden 

 yellow pigment, while others form a chocolate brown. Some in 

 water produce green and various other colored pigments. Thus 



