| Abstrakt: |
The uncoperon of Escherichia coliwas split into two fragments by the restriction endonuclease HindIII. The operator-proximal portion was cloned into plasmid pACYC184, forming plasmid pAN51, which included the genes uncB, uncE, and uncA. When plasmid pAN51 was used as template in an in vitro transcription/translation system, the α subunit (from the uncAgene) and δ subunit of the F1adenosine triphosphatase (ATPase) were formed. In addition, three polypeptides of molecular weights 18,000, 17,000, and 14,000 were formed, and the significance of these polypeptides is discussed. The operator-distal portion of the uncoperon was also cloned into plasmid pACYC184, forming plasmid pAN36, which included the uncDand uncCgenes. When this plasmid was used as template in an in vitro transcription/translation system, the β subunit (from the uncDgene) and the ε subunit (from the uncCgene) of the F1ATPase were formed. A polypeptide of a molecular weight similar to the ε subunit but of different net charge was also formed. Plasmid pAN45, carrying the complete uncoperon, was isolated after digestion of a mixture of plasmids pAN51 and pAN36 with the restriction endonuclease HindIII and then religation with T4 deoxyribonucleic acid ligase. It was concluded that a HindIII restriction site occurred within the newly described uncGgene, which was shown, by complementation studies with Mu-induced mutants, to be located between the uncAand uncDgenes to give the gene order uncBEAGDC. The uncGgene appears to code for the γ subunit of the F1ATPase. |
