ezDNase™ Enzyme - FAQs

View additional product information for ezDNase™ Enzyme - FAQs (11766051)

10 product FAQs found

How can I quantify the ssDNA in samples that contain both ssDNA and dsDNA, using the Qubit ssDNA Assay Kit (Cat. No. Q10212)?

Unfortunately, it is not possible to efficiently measure the ssDNA content in a sample that also contains dsDNA with the Qubit ssDNA Assay Kit (Cat. No. Q10212). The dye in the Qubit ssDNA Assay kit binds to both ssDNA and dsDNA.

It is possible to treat the sample with a DNase that only degrades dsDNA, such as theezDNase Enzyme (Cat. No. 11766051), and measure the ssDNA concentration afterward. However, if all dsDNA is not successfully digested, there is a risk of overestimating the ssDNA content.

The following article describes a PCR-based method to detect ssDNA in dsDNA samples:

Quantitative amplification of single-stranded DNA (QAOS) demonstrates that cdc13-1 mutants generate ssDNA in a telomere to centromere direction

Find additional tips, troubleshooting help, and resources within our Nucleic Acid Purification and Analysis Support Center.

Does the TaqMan Cells-to-CT Express Kit contain reagents for the removal of genomic DNA (gDNA)?

Yes, the TaqMan Cells-to-CT Express Kit includes Express ezDNase which can be added to the Express Lysis Solution for removal of gDNA during cell lysis. Express ezDNase is a double-strand specific, heat-labile DNase that will only digest gDNA, making it compatible with the downstream reverse transcription reaction. The enzyme is automatically inactivated during a heat kill step included in the reverse transcription program. To avoid the detection of gDNA, we recommend using a TaqMan Gene Expression Assay specifically designed to span an intron-exon boundary. Such assays are designated with an "_m1" suffix. More information can be found here.

Find additional tips, troubleshooting help, and resources within our Real-Time PCR and Digital PCR Applications Support Center.

In your SuperScript IV RT protocols, there is no ezDNase inactivation step. Will active ezDNase affect RNA or the RT reaction?

The Invitrogen ezDNase Enzyme is a novel DNase that is highly specific for double-stranded DNA. It has no activity on single-stranded DNA in RT reactions (primers or probes), or on RNA. The enzyme is also thermolabile—it is inactivated quickly at temperatures typical for the SuperScript IV RT reaction (e.g., 50°C). The additional inactivation step is therefore not required in RT-qPCR applications.

Find additional tips, troubleshooting help, and resources within our PCR and cDNA Synthesis Support Center.

Which SuperScript IV RT format do you recommend for real-time PCR applications?

For RT-qPCR applications we recommend using the Invitrogen SuperScript IV VILO Master Mix (Cat. No. 11756050). The cDNA synthesis reaction setup with this master mix requires fewer pipetting steps and therefore reduces variation in the data. SuperScript IV RT, as a component of the master mix, offers the highest efficiency of cDNA synthesis step compared to competitors’ products.

Find additional tips, troubleshooting help, and resources within our PCR and cDNA Synthesis Support Center.

Are there any significant changes in the SuperScript IV RT protocol compared to the SuperScript III RT protocol?

The only change is that the incubation time for the reverse transcription reaction has been reduced from 50 minutes to 10 minutes. All the other parameters and steps are the same.

Find additional tips, troubleshooting help, and resources within our PCR and cDNA Synthesis Support Center.

Can I get comparable cDNA yield and length using the SuperScript IV RT 10-minute protocol as when using the 50-minute protocol for SuperScript III RT?

When compared with SuperScript III RT (and other manufacturers’ RTs) in a synthesis reaction for a 9 kb cDNA, SuperScript IV RT performed successful synthesis in just 10 minutes and did so with comparable (or improved) yield (as shown by gel band density).

Find additional tips, troubleshooting help, and resources within our PCR and cDNA Synthesis Support Center.

What is the composition of the ezDNase Enzyme (Cat. No. 11766051) buffer?

The composition of the ezDNA Enzyme buffer is proprietary.

Does the substrate of ezDNase Enzyme (Cat. No. 11766051) include DNA, in the context of a DNA-RNA hybrid?

The ezDNase Enzyme is a recombinant double-strand-specific DNase for the fast removal of contaminating genomic DNA from RNA preparations, and it is highly specific without impact on DNA in the context of a DNA-RNA hybrid.

Do you offer a one-step RT-qPCR kit containing SuperScript IV RT?

We have not created a one-step RT-qPCR kit containing SuperScript IV RT for real-time PCR. However, it is included in end-point one-step RT-PCR kits: https://thermofisher.com/ssiv-onestep

We also offer a two-step RT-qPCR kit containing SuperScript IV RT: https://www.thermofisher.com/vilo

For one-step RT-qPCR, we offer a kit with SuperScript III RT: https://www.thermofisher.com/order/catalog/product/117320200

Do I need to DNase treat my RNA when using SuperScript IV RT?

Yes, DNase treatment is highly recommended when any amplifcation will be performed after cDNA synthesis. Our ezDNase enzyme protocol is an extremely simplified genomic DNA removal step that occurs immediately before reverse transcription, and does not require re-purification of the RNA. This dramatically reduces the time of the entire reverse transcription protocol and reduces RNA loss or damage that can occur during conventional DNase treatment.