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.

QIAGEN

Products

UDGase (2500 U)

StableScript (250 U)

UDGase (500 U)

EnzScript (Rev Trans) (10000 U)

RNAse Inhibitor (20000 U)

Exonuclease III (50000 U)

DNA Polymerase I (5000 U)

Klenow (3'-5' exo-) (HC) (10000 U)

Klenow (3'-5' exo-) (low conc) (10000 U)

T4 DNA Polymerase (exo) (2000 U)

Taq-B DNA Polymerase (10000 U)

T4 Gene 32 Protein (1 mg)

T4 Polynucleotide Kinase (10000 U)

End-Repair Mix (HC) (75 rxn)

End-Repair Mix (LC) (200 rxn)