Proteinase K

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SKU: 786-035-XX Category:
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Proteinase K (also protease K, endopeptidase K, peptidase K or Tritirachium  alkaline phosphatase) (EC is a non-specifc, broad spectrum serine protease that is isolated from the saprophytic fungus Tritirachium album. 
Proteinase K is routinely used for the purification of target material from contaminating proteins, for the isolation of RNA and DNA and to inactivate other protein enzymatic activities. Proteinase K exhibits high activity in the presence of SDS, urea and EDTA. This allows the use of EDTA in the purification of DNA or RNA to inhibit calcium dependent nucleases.
Proteinase K, Lyophilized
The dry, lyophilized powder is highly soluble (>50mg/ml); however, stock solutions are normally 20mg/ml. The proteinase K is completely RNase and DNase free and has a specific activity of >30 units/mg at 37°C. The recommended storage buffer is 20mM Tris-HCl (pH7.4), 1mM CaCl2, 50% glycerol. Proteinase K is stable for 1 year in this storage buffer, recommended storage is -20°C.
LongLife™ Proteinase K
LongLife™ Proteinase K is an optimized, 5mg/ml solution that is free from all nuclease contamination. The specific activity is >30 units/mg at 37°C. The buffering conditions used ensure that the enzyme retains its full activity and offers convenience to the researchers. LongLife™ Proteinase K is stable for a year if stored correctly.
All of our LongLife™ enzyme preparations have a long shelf life and no weighing or buffer preparation is needed; simply take an aliquot and add to your sample. LongLife™ enzyme preparations contain cofactors necessary for optimal enzymatic activity. Supplied in suspension form and when stored properly have a one year shelf life.
All LongLife™ Enzymes Available: 
LongLife™ Zymolyase® for digestion of yeast & fungal cell walls
LongLife™ Lysozyme for digestion of bacterial cell walls
LongLife™ Proteinase K for digestion of proteins in nucleic acid preparations
LongLife™ Nuclease for removal of nucleic acids
LongLife™ RNase for digestion of RNA
LongLife™ DNase for digestion of DNA
LongLife™ PE LB Lysozyme for digestion of bacterial cell walls & reduction of viscosity build-up due to
presence of nucleases (fully compatible with our PE LB™Systems)




  • Broad spectrum serine protease
  • Highly Soluble: >50mg/mL
  • DNase and RNase free
  • Specific Activity: >30units/mg at 37°C
  • Inhibited by PMSF or DFP



Suggested Application



Reference Sample

20mM Tris-HCl (pH8.0)


Bacterial Genomic DNA Isolation

10mM Tris-HCl, 1mM EDTA, 0.5% SDS (pH8.0)


Mammalian Genomic DNA Isolation from Tissue

10mM Tris-HCl, 25mM EDTA, 100mM NaCl, 1% SDS (pH8.0)


Plant Genomic DNA Isolation from Tissue

100mM Tris-HCl, 100mM EDTA, 250mM NaCl, 1% Sarkosyl (pH8.0)


Inactivation of Calf Intestinal Alkaline Phosphatase

10mM Tris-HCl, 5mM EDTA, 50mM NaCl, 1mM DTT, 0.5% SDS (pH7.9)


Denaturation of Proteins

50mM Tris-HCl, 1mM CaCl2, 3mM DTT, 2M Urea (pH8.0)


PCR Buffer

10mM Tris-HCl, 1.5mM MgCl2, 0.1% Triton® X-100 (pH8.8)






Additional information


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