Elastase, like trypsin and chymotrypsin, is a serine protease that also hydrolyses amides and esters It is produced in the pancreas as an inactive zymogen, proelastase, and activated in the duodenum by trypsin. Elastase is distinctive in that it acts upon elastin.
EC 3.4.21.4
Source: Porcine pancreas
Activity: ~115-125 units per mg of protein on the substrate elastin-orcein.
Purity: Chromatographically purified, salt-free free of trypsin, chymotrypsin, lipase, alpha-amylase and the carboxypeptidases. High purity elastase is isolated from 2X crystallized elastase. The 2X elastase is chromatographed on DEAE-cellulose at pH 8.8 to remove anionic non-specific protein. The elastolytic effluent is chromatographed at pH 5.0 on CM-cellulose recovering the highest specific activity by elution with salt gradient. Trace trypsin, and chymotrypsin contamination is removed by affinity chromatography. Homogenous on 15% polyacrylamide electrophoresis at pH 4.5 and on gel exclusion chromatography (G200) at pH 5.0 and 25°C.
Trypsin; Not detected on 0.5mg elastase after more than 24 hour incubation at 25°C on the substrate N-benzoyl-DL-arginine-pNA (BAPNA).
Alpha-chymotrypsin: Not detected on 0.5mg elastase after more than 24 hr. incubation at 25°C on the substrate N-benzoyl-L-tryosine ethyl ester (BTEE).
Form: Lyophilized, water soluble powder.
Unit Definition: One unit will solubilized 1mg of elastin in 20 minutes at pH 8.8 and 37°C (11). ≥ 9 units per mg of protein on the substrate Suc-Ala-Ala-Ala-pNA.One unit will hydrolyze 1umole per minute at pH 8.3 and 25°C.
Unit Definition: One unit is defined as the amount of enzyme that produces a change in absorbance at 340nm at 25°C using triolein as substrate under colipase saturation, pH 9.2.
Storage and Stability:Store at 5°C. Stable 9-12 months with no decrease in activity.
