Transcription and processing of tRNA in prokaryotes:

The rRNA transcription units in E. coli hold some tRNA genes which are processed and transcribed at the time of rRNA transcription. The other tRNA genes occur in clusters of up to seven tRNA sequences separated through spacer regions. Subsequent transcription through the single prokaryotic RNA polymerase, the

Figure:  Transcription and processing of tRNA in prokaryotes.

mainly  RNA  transcript  folds  up  into  the  characteristic  stem-loop  structures and is then processed in an ordered series of cleavages through ribonucleases (RNases)  that release and trim the tRNAs to their final lengths. The trimming  and cleavage reactions  at the 5'  and 3'  ends of the precursor  tRNAs  included RNases D and E, F and P. RNases E, F and P are endonucleases  cutting the RNA within,  whilst  RNase  D is an trimming , exonuclease  the ends of the tRNA molecules.