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Proteinase K - lyophilized

Crystallization grade model protein

Endopeptidase K

Cat. No. Amount Price (EUR) Buy / Note
CO-404 100 mg 240,00 Add to Basket/Quote Add to Notepad

Proteinase K crystals grown in 1.2 M Ammonium Sulfate, 0.1 M Tris-HCl pH 8.0.

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

CAS#: 39450-01-6

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 [1]. 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]:

  • 1.2 M Ammonium Sulfate, 0.1 M Tris-HCl pH 8.0
  • 1.0 M NaNO3,100 mM citrate buffer pH 6.5

Selected References:
[1] Larson et al. (2009) High-resolution structure of proteinase K cocrystallized with digalacturonic acid. Acta Cryst. F 65:192.
[2] 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.
[3] Wang et al. (2006) What can be done with a good crystal and an accurate beamline? Acta Cryst. D 62:1475.