Crystallization grade model protein
For in vitro use only!
Shipping: shipped at ambient temperature
Storage Conditions: store at 4 °C
Shelf Life: 12 months
Molecular Weight: 28.93 kDa
EC number: 254-457-8
Form: lyophilized powder
Proteinase K is a fungal protease from Tritirachium album. It belongs to the subtilisin family with the classic catalytic triad of Asp39-His69-Ser224 at its active site . The enzyme is very stable over a wide pH-range, at various salt concentrations and is even active in SDS concentrations up to 0.5%.
Proteinase K can be utilized as model protein in crystallization experiments and X-ray structure analysis.
Source: Tritirachium album
Warm the Proteinase K powder to room temperature before opening.
We recommend to resuspend the enzyme in 50 mM HEPES pH 7.0 to a final concentration of 10-20 mg/ml.
Crystals can be grown using the sitting drop or hanging drop vapor diffusion method.
Following crystallization conditions are suggested for Proteinase K crystal growth [2,3]:
 Larson et al. (2009) High-resolution structure of proteinase K cocrystallized with digalacturonic acid. Acta Cryst. F 65:192.
 Müller-Diekmann (2007) On the routine use of soft X-rays in macromolecular crystallography. Part IV. Efficient determination of anomalous substructures in biomacromolecules using longer X-ray wavelengths. Acta Cryst. D 63:366.
 Wang et al. (2006) What can be done with a good crystal and an accurate beamline? Acta Cryst. D 62:1475.