NOTE ON THE EFFECT OF X-RADIATION ON 

 FERTILIZIN.i 



A. RICHARDS AND A. E. WOODWARD. 



The observations of one of the writers that x-rays would 

 produce changes in the activity of certain enzymes suggested 

 that these rays might perhaps be effective in bringing about 

 changes in the action of cell extractives, particularly of fertilizin, 

 the descriptions of which by Lillie and Glaser appeared at the 

 beginning of the summer. The opportunity was presented to 

 test this suggestion during the past summer at Woods Hole, 

 since the one of us carried on studies on the effect of x-rays on 

 some marine eggs and the other continued the work on fertilizin 

 of Arbacia begun by Glaser. This note gives a summary of the 

 results. It is realized by the writers that the study is by no 

 means a complete one, but it is believed by them that publication 

 is justified in view of the facts that the experiments give clear 

 evidence on the main point under investigation and that there 

 is at present no prospect of opportunity for their further work on 

 the problem. 



In taking up these experiments the writers felt that if it should 

 be shown that x-radiation influences the activity of the cell 

 extractive called fertilizin, that fact would be of interest from 

 several view points: (i) without regard to the nature of fertilizin 

 or its r61e in the fertilization of the egg, it is a substance derived 

 from the eggs which has the property of being definitely modified 

 by those external agents of which experimental use may be made ; 

 (2) in cell extractives, of which fertilizin is an example, there is a 

 basis for the action of x-rays upon living cells, and doubtless the 

 marked effects of the rays upon tissues is partially due to such 

 action; (3) the modifiability of its activity by radiation is an 

 interesting property of fertilizin ; (4) this property may serve as a 

 point in determining the relation of fertilizin to enzymes. 



1 Contribution from the Marine Biological Laboratory at Woods Hole, and from 

 the Zoology departments of the University of Texas (No. 123) and of the University 

 of Michigan. 



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