RNase I degrades single-stranded RNA to nucleoside 3 monophosphates via 2,3 cyclic monophosphate intermediates by cleaving between all dinucleotide pairs,2,3 unlike RNase A, which cleaves only after cytosine and uridine. In addition, the enzyme is completely inactivated by heating at 70C for 15 minutes, eliminating the requirement to remove the enzyme prior to many subsequent procedures.