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Gene Recombination in Escherichia Coli 



JOSHUA LEDERBERG a7ld EDWARD L. TATUM 



Reprinted by authors' and publisher's permis- 

 sion from Nature, vol. 158, 1946, p. 558. 



In selectijjg papers for this vohmie I have deliberately ojjiitted iriost 

 of the papers published prior to 1952 in the highly specialized field 

 of study known as '''microbial genetics,'' because of the availability of 

 the book ^'Papers in Microbial Genetics,''' edited by J. Lederberg arid 

 published by the University of Wisconsin Press. That book serves 

 the same function for that area of genetics as does this volume for 

 much of the rest of the field. 



Omitted fro?n that volume, however, is this short note on the 

 occurrence of sex in a bacterium. It is of far-reaching importance in 

 that it is the initial announcement of an entirely new and unsuspected 

 phenomenon. The importayit role of sex in hereditary and evolu- 

 tionary processes has been evident from the time of publication of 

 the first paper i?i this series by Mendel, and has been repeatedly 

 emphasized by Sutton, Bridges, Sturtevant, and Morgan, among 



