The Biochemistry 

 of Lysogeny 



ERNEST BORER 



Hope, rather than experience, prompted the title of this essay. 

 "Chemical gropings in lysogeny" would more accurately describe the 

 writer's contribution to this engrossing biological phenomenon. The 

 bold, perhaps brash, title thus merely serves to delineate an ultimate 

 goal: an understanding of the lysogenic mechanism at the molecular 

 level. Such a goal may remain asymptotic to several generations of 

 biochemists; nevertheless, the writer believes that biochemists can 

 already occupy themselves fruitfully with this phenomenon not only 

 with the aim of contributing to an understanding of lysogeny but, 

 equally, with the hope that a study of lysogeny will contribute to our 

 store of knowledge of biochemistry. A paramount problem in bio- 

 chemistry today is the elucidation of the structures of macromolecules 

 and their correlation with biological function, including the replication 

 of those macromolecules. The writer feels that such problems can be 

 more fruitfully approached at present from a study of the biological 

 functions of the simplest of the self-reproducing systems than from 

 the application of the tools of the organic chemist to isolated fragments 

 of cellular mechanisms. In other words, biological function can reveal 

 chemical structure and mechanism, but the process, at the level of 

 macromolecules, is well-nigh irreversible at present. 



If the reader demands evidence of this, let him consider how little 

 biochemistry has contributed to a knowledge of the mechanism of 

 genetics and how much microbial genetics has contributed to our under- 

 standing of intermediary metabolism. Indeed, even in classical organic 

 chemistry, function has been the key to structure and not the reverse. 

 Long before the elucidation of organic structures from X-ray analysis 

 was dreamed of, Kekule derived the structure of the benzene ring from 

 its functions, from its behavior during substitution reactions. 



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