RNAse Inhibitor (20000 U)

QIAGEN's RNase Inhibitor protects RNA integrity in critical workflows by neutralizing RNases through high-affinity binding without interfering with other enzymatic activities. It is a recombinantly expressed protein produced in E. coli as a fusion of the porcine ribonuclease inhibitor gene with a proprietary 22.5 kDa protein tag. The native inhibitor is a large (~450 residues, ~50 kDa), acidic (pI ~4.7), leucine-rich repeat protein that acts as a potent noncompetitive inhibitor of pancreatic-type ribonucleases such as RNase A, RNase B and RNase C, forming some of the tightest known non-covalent complexes in biology. It does not interfere with the activities of polymerases or reverse transcriptases.

The product is supplied in 20 mM Hepes-KOH, 50 mM KCl, 8 mM DTT, 50% glycerol, pH 7.5 at 25°C, with storage at –25°C to –15°C. Quality specifications include >99% purity, a specific activity of 53,333 U/mg, single-stranded exonuclease activity of <5.0% released per 2000 U, double-stranded exonuclease activity of <1.0% released per 2000 U, no conversion in double-stranded endonuclease assays per 2000 U, <10 copies of E. coli DNA contamination per 2000 U, and no detectable non-specific RNase contamination per 2000 U.

The inhibitor is active below 50°C under nondenaturing conditions, with optimal activity between 25°C and 37°C, and is effective within a pH range of 5.0–8.0. It is typically added to the reaction mixture at a final concentration of 1 U/μL before potentially RNase-contaminated components, and can be inactivated by heating at 65°C for 10 minutes if needed. A glycerol-free (lyophilization-ready) format is also available. Applications include RNA isolation and purification, RNA storage, cDNA synthesis, RT-PCR and RT-qPCR, in vitro transcription and translation (including workflows with T7 RNA Polymerase), RNA-Seq library preparation, Northern blotting, CRISPR guide RNA production, monoclonal antibody production, enzyme assays, and ribonuclease characterization.