Proteinase K

Proteinase K is a non-specific serine protease first discovered in the fungus Engyodontium album. This protease hydrolyzes various peptide bonds, including keratin (hence the 'K' in the name). Its broad specificity makes this enzyme useful in the protein degradation and cleanup of enzymatic reactions and cell lysates. An endopeptidase with a molecular weight of 28.9 kDa, Proteinase K has its active site at positions Asp39, His69, and Ser224. It is active in wide pH and temperature ranges, showing optimal activity between 20 and 60°C and at a pH between 7.5 and 12.0. Calcium ions help with the thermostability of Proteinase K but are not essential for function. The enzyme is also active in many buffers, even those containing chelating agents. It is especially useful in molecular biology for removing contaminants from nucleic acid preparations. Visit the supplier page for more enzyme information.