What is proteinase K solution?
What is proteinase K solution?
Proteinase K, produced by the fungus Tritirachium album Limber, is a serine protease that exhibits broad cleavage activity. It cleaves peptide bonds adjacent to the carboxylic group of aliphatic and aromatic amino acids and is useful for general digestion of protein in biological samples.
How do you make a proteinase K solution?
Proteinase K is prepared commonly as a 20 mg/ml stock solution in sterile water (stable for 1 year at −20°) or in a solution of 50 mM Tris, pH 8.0, 1 mM CaCl2 (stable for months at 4°).
What type of molecule is proteinase K?
serine protease
Proteinase K is a subtilisin-related serine protease that hydrolyzes a variety of peptide bonds and is frequently used to cleanup enzymatic reactions or cell lysates.
What is the purpose of proteinase K in the lysis solution?
Proteinase K is used during DNA extraction to digest many contaminating proteins present. It also degrades nucleases that may be present in DNA extraction and protects the nucleic acids from nuclease attack.
How to calculate the molecular weight of Proteinase K?
Heat Inactivation 95°C for 10 min Molecular Weight Calculated: 28.9 kDa Unit Assay Conditions 0.5–2 μg of Proteinase K is incubated with 2% denatured hemoglobin solution for 10 minutes at 37°C (pH 7.5).
Do you need a stock solution for proteinase K?
We have to prepare a stock solution as well as working proteinase K solution depending upon our requirements. The proteinase K powder lyophilised either into the water or into the buffer. If it is lyophilised into the buffer, we do not need to add any other extra ingredients such as buffer or glycerol.
When is proteinase K most active in the body?
It is highly active between pH 7.5 and 12.0 and temperatures between 20 and 60°C (1,2). Proteinase K is also active in chelating agents such as EDTA (4) and activity is stimulated in up to 2% SDS or 4 M urea (3).
How does proteinase K help in DNA extraction?
In combination with these chemicals, proteinase K increases the efficiency of the result by increasing the purity of the DNA. Further, proteinase K works incredibly good along with several other enzymes such as trypsin, chymotrypsin and RNase. It depends on us, what types of tissue we are using for the DNA extraction.