Cat. No. / ID: Not Applicable
The Ribonuclease A (RNase A) is a 13.7 kDa (monomer) endoribonuclease isolated from bovine pancreas, which selectively cleaves single-stranded RNA 3’ next to pyrimidine residues (cytosine, uracil). It degrades RNA to cyclic nucleotide monophosphates to 5’- OH and 2’-, 3’-cyclic monophosphate. The enzyme exhibits no endonuclease or exonuclease activity toward DNA substrates. RNase A removes RNA during the isolation procedures of plasmid and genomic DNA.
It is supplied with 1–10 mg/mL by resuspending in 10 mM Tris-HCl (pH 7.5), 15 mM NaCl, 50% (v/v) glycerol or in TE buffer.
One unit of activity is defined as the amount of enzyme which causes the hydrolysis of RNA to yield a velocity constant, k=1, at 25°C and pH 5.0
|Activity||94.5 U/mg (Kunitz)|
|DNase contamination||None detected|
|Protease contamination||None detected|
RNase A is very active under a wide range of reaction conditions and is difficult to inactivate. At low salt concentrations (up to 100 mM NaCl), the RNase A cleaves single- and double-stranded RNA as well as an RNA strand in RNA-DNA hybrids. However, under high salt concentrations (>300 mM NaCl), RNase A specifically cleaves single-stranded RNA.
RNase A cleaves specifically at the 3′-side of pyrimidine (uracil or cytosine) phosphate bonds. Ribonucleases do not hydrolyze DNA because the DNA lacks 2′-OH groups essential for forming cyclic intermediates. The enzyme is active under a wide range of reaction conditions. At low salt concentrations (0 to 100 mM NaCl), RNase A cleaves single-stranded and double-stranded RNA as well the RNA strand in RNA-DNA hybrids. However, at NaCl concentrations of 0.3 M or higher, RNase A specifically cleaves single-stranded RNA. RNase is supplied as a lyophilized powder.
This is used for applications such as: