Fig. 1.

Schematic diagram of ribonucleases and RNA processing enyzmes in bacteria

Exoribonucleases process RNA to oligonucleotides from the 3′ and 5′ directions. Endoribonucleases process single stranded (SS) or double stranded (DS) RNA molecules, releasing additional targets for processing by exoribonucleases. RNA modifying enzymes can alter the rates of RNA processing by additional ribonucleases. Enzymes with homologs in E. coli, B. subtilis and Synechococcus sp. PCC 7002 (PCC 7002), respectively, are shown with a closed back circle. An open black circle indicates absence of a homolog in the corresponding strain.