Proteinase K

Proteinase K is a serine protease with wide cleavage activity, which can cleave the carboxyl-terminal peptide bond of aliphatic and aromatic amino acids. Its relative molecular weight is about 29.3 kDa. Proteinase K is widely used in the preparation of chromosomal DNA for pulse electrophoresis, Western blotting, and the removal of a nuclease from DNA and RNA preparation. Denaturant such as SDS (1%) can improve its activity. In addition, the common working concentration is 50-100 μg/mL, and the specific working concentration is according to whether the buffer contains SDS, urea, pH, temperature, and other factors.