SuperScript™ IV Reverse Transcriptase (RT) is a proprietary MMLV mutant with superior robustness and reliability in RT reactions. It is significantly improved over SuperScript™ III in inhibitor resistance, processivity, and reaction speed, while retaining all the benefits of the previous enzyme, including increased thermostability, highly efficient full-length cDNA synthesis, and reduced RNase activity. SuperScript™ IV RT is designed to provide reliable, consistent, and fast cDNA synthesis in the presence of inhibitors found in a wide variety of samples that cause other currently available RTs to perform inefficiently.

SuperScript™ IV RT is the top choice for all RT-PCR and qRT-PCR applications in the SuperScript™ product family. We recommend it especially when reproducibility and reliability is the primary concern and when inhibitors in the RNA sample may interfere with cDNA synthesis, leading to biases in gene expression studies.

Features of SuperScript™ IV Reverse Transcriptase include:
• Significantly improved resistance to a variety of inhibitors that can interfere with cDNA synthesis
• Robust and specific cDNA synthesis in a wide range of sample types
• A faster reverse transcriptase reaction that reduces the incubation time from >50 minutes to 10 minutes
• Significantly better processivity compared to SuperScript™ III RT

Source
Purified from E. coli expressing the pol gene of M-MLV, modified to increase thermostability and half-life, processivity, inhibitor resistance and to reduce RNase H activity.

Performance and quality testing
Endodeoxyribonuclease, exodeoxyribonuclease, and ribonuclease assays; and yield and length of cDNA product.

Unit definition
One unit of SuperScript™ IV RT is the amount of enzyme required to incorporate 1 nmole of deoxyribonucleotide into acid-precipitable material in 10 min at 37°C using poly(A) oligo(dT)_12-18 as a template/primer.

Unit reaction conditions
50 mM Tris-HCl (pH 8.3), 4 mM MgCl², 10 mM DTT, 50 mM KCl, 0.5 mM dTTP, 0.4 MBq/mL [³H]-dTTP, 0.4 mM poly(A) oligo (dT)_12-18 and enzyme in 20 μl for 10 min at 37°C.