Functional genetic expression of eukaryotic DNA in Escherichia coli.

We have isolated a segment of DNA from the eukaryote Saccharomyces cerevisiae (baker's yeast) as a viable molecular hybrid of bacteriophage lambda DNA which, when integrated into the chromosome of an E. coli histidine auxotroph, allows this bacterium to grow in the absence of histidine. The nonrevertable, histidine auxotroph lacks the enzymatic activity of imidazole glycerol phosphate (IGP) dehydratase (EC 4.2.1.19). From genetic experiments, we conclude that expression of the segment of yeast DNA results in the production of a diffusible substance and that transcription necessary for the complementation is most likely initiated from the segment of eukaryotic DNA.