Synonym: Endopeptidase K
CAS Number: 39450-01-6
EC Number: 254-457-8
Enzyme Commission (EC) Number: 3.4.21.64
MDL number: MFCD00132129
Biochem/physiol Actions
Proteinase K is a stable and highly reactive serine protease. Evidence from crystal and molecular structure studies indicates the enzyme belongs to the subtilisin family with an active-site catalytic triad (Asp39-His69-Ser224). It is stable in a broad range of environments: pH, buffer salts, detergents (SDS), and temperature. In the presence of 0.1-0.5% SDS, proteinase K retains activity and will digest a variety of proteins and nucleases in DNA preparations without compromising the integrity of the isolated DNA.
Unit Definition
One unit will hydrolyze urea-denatured hemoglobin to produce color equivalent to 1.0 µmole of tyrosine per min at pH 7.5 at 37 °C (color by Folin-Ciocalteu reagent).
Application
Useful for the proteolytic inactivation of nucleases during the isolation of DNA and RNA.
Removal endotoxins bound to cationic proteins such as lysozyme and ribonuclease A.
Reported useful for the isolation of hepatic, yeast, and mung bean mitochondria Determination of enzyme localization on membranes.
Treatment of paraffin embedded tissue sections to expose antigen binding sites for antibody labeling.
Digestion of proteins from brain tissue samples for prions in Transmissible Spongiform Encephalopathies (TSE) research.
Legal Information
PicoGreen is a registered trademark of Life Technologies
Quality Level: ELITE
Grade: for molecular biology
Product Line: BioUltra
Form: lyophilized powder
Mol. Wt.: mol wt 28.93 kDa
Composition: Protein, =90% biuret
Impurities: =500 pg/mg DNA (PicoGreen® assay)
Foreign Activity: DNAse, Nickase and RNAse, none detected
Storage Temp.: -20°C