Transfer RNA genes between 16S and 23S rRNA genes in rRNA transcription units of E. coli.

We have identified genes for tRNAGLU/2 on the transducing phages o80d3ilvsu7+ (see Ohtsubo et al., 1974) and lambdarifd18 (Kirschbaum and Konrad, 1973), and a gene for tRNAlle/1 on the transducing phage o80rifr (Konrad, Kirschbaum, and Austin, 1973). All these phages have previously been shown to carry genes for rRNA (Ohtsubo et al., 1974; Lindahl et al., 1975; Jaskunas et al., 1975a). We have analyzed the position of these tRNA genes by hybridizing purified RNAs to restriction fragments of the phage DNA. The tRNA genes are located inside the rRNA transcription unit in the spacer region between the 16S and 23S rRNA genes.