Assay of Bacillus subtilis Ribonuclease Activity In Vitro.

Ribonucleases can cleave RNAs internally in endoribonucleolytic mode or remove one nucleotide at a time from either the 5' or 3' end through exoribonuclease action. To show direct implication of an RNase in a specific pathway of RNA maturation or decay requires the setting up of in vitro assays with purified enzymes and substrates. This chapter complements Chapter 24 on assays of ribonuclease action in vivo by providing detailed protocols for the assay of B. subtilis RNases with prepared substrates in vitro.