804 Arthur B. Pardee 



through inter-related syntheses into large molecules; and the 

 rates of syntheses of the latter might be determined by the 

 supply of least readily available building blocks. 



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DISCUSSION 



Rocker: Dr. Pardee, would you say that in the wild-type organism 

 there is anywhere close to 5 x 10-' m cytidylic acid accumulation? Does 

 the intracellular concentration ever exceed the Ki value? 



Pardee : If synthesis were not shut off, cytidylic acid would accumulate 



