CATALYSIS: THE GUIDE OF LIFE 129 



before material attacks on the tooth had resulted. The fluorine proba- 

 bly also gives the tooth a denser and less readily attacked structure. 

 "Bone gives an x-ray diffraction pattern similar to that of the mineral 

 apatite, the unit structure of which contains Ca 10 (PO 4 ) c F 2 . Various 

 substitutions, such as (OH)- for F - and Mg +2 for Ca +2 , are known to 

 occur in the apatite lattice without producing significant changes in 

 the diffraction pattern." 77 



Wide use is made of ethylene gas (about 1 part per 1000 of air) to 

 "color up" fruits and vegetables which must be shipped more or less 

 "green" in order to stand handling and avoid spoilage. Bananas, 

 melons, pineapples, persimmons, tomatoes, oranges, apples, pears, etc., 

 are so treated, the natural coloring processes being greatly accelerated. 

 Celery may be thus blanched, and the hulls loosened from "stick-tight" 

 walnuts. The diverse changes seem to be dependent upon initiating 

 or facilitating specific enzymic changes. 



Spraying apple trees with soluble thiocyanates, though it causes 

 "spray burn" and a chlorotic condition of the leaves, tends to increase 

 the red color of the fruit (blush) and to turn the green ground color 

 toward yellow, both features desirable to consumers. 78 The red color 

 is due to idaein, a glucoside which, on hydrolysis, yields cyanidin and 

 galactose. There is some evidence that spraying apples with naph- 

 thaleneacetic acid and related compounds tends, with some varieties, 

 to reduce the percentage of windfalls, apparently by firming the 

 stems. 79 



D. W. Wooley has shown 80 that the mouse requires a new "vitamin" 

 for normal growth and maintenance of hair. The facts indicate "that 

 the mouse anti-alopecia factor is inositol or its derivatives. They sug- 

 gest that inositol exists in liver in alkali-labile combination with a 

 large molecule which renders the former non-dialyzable." 



These scattering instances, which might be multiplied many times, 

 illustrate how devious, various, and potent may be the effects of small 

 amounts of substances, which, until comparatively recent times, were 

 generally considered "negligible" in reports of chemical analyses. 

 Their effects are often expressed through catalysts. 



Biocatalyst Systems or Chains 



It is we who are simple, not nature. The physico-chemical 

 happenings at various structural levels, which underlie the phe- 

 nomena we observe, are numerous, intricate, often obscure, some- 

 times unsuspected. The complications involved in the structure, 

 lability, and functioning of individual enzymes are magnified in 

 cells, tissues, and organisms, where groups of catalysts and cooper- 

 ative chemicals form chains or systems which have not yet been 



