Proteinasa K from Tritirachium album

Útil para la inactivación proteolítica de nucleasas durante el aislamiento de ADN y ARN.

Útil para la inactivación proteolítica de nucleasas durante el aislamiento de ADN y ARN.
Elimina las endotoxinas que se unen a las proteínas catiónicas como la lisozima y la ribonucleasa A.
Se ha comunicado que es útil para el aislamiento de mitocondrias hepáticas, de levadura y de frijol mung
Determinación de la localización de las enzimas en las membranas
Tratamiento de cortes de tejido incluidos en parafina para exponer los sitios de unión de antígenos para el marcado con anticuerpos.
Digestión de proteínas de muestras de tejido cerebral para investigación de los priones en las encefalopatías espongiformes transmisibles (EET).

Proteinase K is useful for the proteolytic inactivation of nucleases during the isolation of DNA and RNA. It is used for the removal of endotoxins bound to cationic proteins such as lysozyme and ribonuclease A. It is also useful for the isolation of hepatic, yeast, and mung bean mitochondria and is used to determine enzyme localization on membranes. Furthermore, it is used for the treatment of paraffin embedded tissue sections to expose antigen binding sites and for digestion of proteins from brain tissue samples. Product P8044 is provided as a lyophilized powder.

The enzyme from Sigma has been used to degrade complex I (NADH:ubiquinone oxidoreductase) prior to extraction of ubiquinone from Yarrowia lipolytica. It has been used to examine the effect of Proteinase k on Pythium ultimum. It has also been used to maximize the variety of peptide bonds hydrolyzed in the sediment slurry without autolytic production of amino acids from the enzyme itself.

La proteinasa K es una serín proteasa estable y muy reactiva. La evidencia procedente de estudios de la estructura cristalina y molecular indica que la enzima pertenece a la familia subtilisina con una tríada catalítica en el sitio activo (ASP³⁹-HIS⁶⁹-ser²²⁴). Es estable en una amplia variedad de entornos: pH, sales amortiguadoras, detergentes (SDS) y temperatura. En presencia de SDS al 0,1 - 0,5 %, la proteinasa K conserva su actividad y digerirá una variedad de proteínas y nucleasas en preparaciones de ADN sin comprometer la integridad del ADN aislado.

Proteinase K is highly active towards native proteins. It has a broad specificity and degrades many proteins even in the native state. It mainly cleaves the peptide bond adjacent to the carboxyl group of aliphatic and aromatic amino acids with blocked α-amino groups. The optimum pH is between 7.5-9.0 and the isoelectric point is 8.9. Ca²⁺ (1-5 mM) is required for activation. Proteinase K is inhibited by diisopropyl fluorophosphate (DFIP), and phenylmethanesulfonyl fluoride (PMSF).

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).