Physical linkage and transcriptional orientation of the tdc operon on the Escherichia coli chromosome

The physical and genetic structure of 37 kilobases of DNA encopassing the tdc region at 68.3 min of the Escherichia coli chromosome was determined by DNA sequence analysis and restriction mapping. Reexamination of new data concerning the direction of transcription of the tdc operon revealed that in strain W3110 the tdc region is located on a transposable segment of DNA.