New England Biolabs, R0744S, PsiI-v2

PsiI-v2 has been reformulated with Recombinant Albumin (rAlbumin) beginning with Lot #10258634. Related Categories Restriction Endonucleases P R Applications DNA Preparation,, DNA Analysis,, Restriction Enzyme Digestion Specification Unit Definition One unit is defined as the amount of enzyme required to digest 1 µg of λ DNA in 1 hour at 37°C in a total reaction volume of 50 μl. Reaction Conditions 1X rCutSmart™ Buffer Incubate at 37°C 1X rCutSmart™ Buffer 50 mM Potassium Acetate 20 mM Tris-acetate 10 mM Magnesium Acetate 100 µg/ml Recombinant Albumin (pH 7.9 @ 25°C) Activity in NEBuffers NEBuffer™ r1.1: 25% NEBuffer™ r2.1: 50% NEBuffer™ r3.1: 10% rCutSmart™ Buffer: 100% Diluent Compatibility Diluent B Storage Buffer 10 mM Tris-HCl 300 mM NaCl 1 mM DTT 0.1 mM EDTA 500 µg/ml Recombinant Albumin 50% Glycerol pH 7.4 @ 25°C Heat Inactivation 65°C for 20 minutes Methylation Sensitivity dam methylation: Not Sensitive dcm methylation: Not Sensitive CpG Methylation: Not Sensitive FAQ Q: When is star activity a concern? A: Star activity is of concern if extra banding can cause misinterpretation of results in genotyping and mutational analysis procedures. Experimental design can promote star activity. Small reaction volumes are more likely to contain glycerol concentrations of 5% or greater, a condition known to increase star activity. A 5% glycerol concentration occurs when setting up a double digest in a 20 µl reaction using 1 µl of each enzyme. Overnight digests are more likely to generate star activity. For tips on avoiding star activity, please click here. Q: Which NEB restriction enzymes are supplied with Gel Loading Dye, Purple (6X)? A: All HF-restriction enzymes and most NEB non-HF restriction enzymes are supplied with Gel Loading Dye, Purple (6X). The non-HF restriction enzymes that come supplied with purple dye are: AatII AsiSI BsmBI-v2 EagI MboI NlaIII PvuI SmaI Acil AvrII BspHI EcoRI MboII NotI RsaI SpeI AfeI BamHI BsrGI EcoRV MluI NspI SacI StuI AflII BbsI ClaI Esp3I FseI MseI PacI SacII AgeI BglII DdeI HaeIII MspI PciI SalI XbaI AluI BsaI DpnI HindIII NcoI PmeI SapI XhoI ApaI BseYI DpnII HpaI NdeI PsiI-v2 SfaNI XmaI ApeKI BsiWI DraI KpnI NheI PstI SfiI XmnI AscI * All HF restriction enzymes are also supplied with Gel Loading Dye, Purple (6X) Q: Is this enzyme sensitive to dam, dcm or mammalian CpG methylation? A: No. This enzyme is not sensitive to dam, dcm, or mammalian CpG methylation. For up-to-date information about methylation sensitivities, please visit Dam-Dcm and CpG Methylation or REBASE. Q: I tested your restriction enzyme on the substrate DNA recommended by NEB, and it appears to be active, however it does not digest my DNA. What could be the reason? A: The quality and cleanliness of the DNA are major factors that can affect enzyme activity. Restriction Enzymes active in rCutSmart® Buffer, but not as active in NEBuffer r2.1 and/or r3.1 (our higher salt buffers), can be inhibited by salt in the reaction. DNA purification procedures that use spin columns can result in DNA solutions with significant levels of salt that can carry over into the reaction and inhibit enzyme activity. To prevent this, we recommend that the DNA solution added to the reaction be no more than 25% of the total reaction volume. This can be attained by adjusting the total reaction volume accordingly. Q: Can you tell me more about the switch from BSA to Recombinant Albumin (rAlbumin) in NEBuffers? A: NEB is excited to announce that we have switched BSA-containing reaction buffers (NEBuffer 1.1, 2.1, 3.1 and CutSmart® Buffer) to Recombinant Albumin-containing buffers (NEBuffer r1.1, r2.1, r3.1 and rCutSmart™ Buffer). We are also in the process of moving all restriction enzyme formulations to contain rAlbumin. We feel that moving away from animal-containing products is a step in the right direction and are able to offer this enhancement at the same price. Q: Can Gel Loading Dye, Purple 6X (B7024) be stored in cold temperatures? A: The recommended storage temperature for Gel Loading Dye, Purple 6X, is room temperature (25°C). Commonly, the SDS may precipitate out of solution when the dye is stored on cold temperatures. This slight precipitate can be dissipated by letting the vial sit at room temperature for an hour, or warming gently for 10 minutes. Mix the vial a few times before use, to bring the solution back to homogeneity. Q: Is Gel Loading Dye, Purple (6X) or Gel Loading Dye, Purple (6X), no SDS compatible with other DNA binding dyes such as SYBR® and GelRed™ during gel electrophoresis? A: Because high affinity nucleic acid binding dyes can affect DNA migration during electrophoresis, post-staining of gels with SYBR or GelRed dyes is highly recommended. However, these dyes can also be used as precast dyes (into the agarose gel). Because the Gel Loading Dye, Purple (6X) has an increased concentration in SDS, some interference may be observed when using SYBR or GelRed as precast dyes. When using these dyes as precast dyes, NEB recommends using our Gel Loading Dye, Purple, No SDS (6X) (NEB #B7025S ) instead. Please follow the recommendations below for both Purple dyes when using SYBR dyes as precast dyes: Reduce the amount of sample DNA loaded to 250 to 500ng, and use 0.5X only of SYBR dyes in precast gels. These dyes are much more sensitive than EtBr. Blown out or smeared bands can be caused by overloading. If using Gel Loading Dye, Purple (6X) B7024S , use TBE instead of TAE buffer, as the SDS interference is increased when using TAE buffer (in the gel and as a running buffer). Use the SYBR dyes as recommended by the manufacturer: add the SYBR dye to the TBE buffer first, then add the SYBR dye/TBE mix to the molten agarose solution. It is preferable to wait a few minutes to add the SYBR dyes to the molten agarose. Adding it to a cooled agarose solution (above gelling temperature, 45°C) produces better results. Always run a freshly made agarose gel, for a single run only. Re-running the gel will yield poor result. Please follow the recommendations below for both Purple dyes when using GelRed dyes as precast dyes: Reduce the amount of sample DNA loaded to 60 to 125ng, and use 0.5X only of GelRed dye in precast gels. This dye is much more sensitive than EtBr. Blown out or smeared bands can be caused by overloading. It is preferable to wait a few minutes to add the GelRed dye to the molten agarose. Adding it to a cooled agarose solution (above gelling temperature, 45°C) produces better results. Always run a freshly made agarose gel, for a single run only. Re-running the gel will yield poor result. SYBR® is a registered trademark of Life Technologies Corporation GelRed™ is a trademark of Biotium