Aprotinin from bovine lung
Cat.NO.:E03710
CAS: 9087-70-1
Appearance：White powder
Molecular formula：C284H432N84O79S7
Molecular Wt：6511.44
Grade：High Purity Grade
Activity：KIU/mg=6000
Storage Temperature：2–8℃，3years.
SOLUBILITY:(Avoid repeated freeze-thaw cycles)
Aprotinin is freely soluble in water (>10 mg/mL) and in aqueous buffers of low ionic strengths. Dilute solutions are generally less stable than concentrated ones. Solution stability also depends on pH; values of 1-12 can be tolerated. Repeated freeze-thaw cycles should be avoided. The Cys14-Cys38 disulfide bridge is readily split by reducing agents like β-mercaptoethanol. Due to its compact tertiary structure, aprotinin is relatively stable against denaturation due to high temperature, acids, alkalies, organic solvents or proteolytic degradation (only thermolysin has been found capable of degrading aprotinin after heating to 60-80 ). The high basicity of aprotinin causes it to adhere to commonly used dialysis tubing and even gel filtration matrices, but the use of acetylaated materials and concentrated salt solutions (e.g.＞0.1 M NaCl in buffer) minimizes the problem. Sterilization may be achieved by filtration through a 0.2 μm filter.
SOLVENT | CONCENTRATION | STORAGE TEMP | % LOSS/TIME |
Sterile water with 0.9% NaCl and 0.9% benzyl alcohol, pH 5.7-6.2 | 10 mg/mL | 0-5 | <4.3%/year |
2.5% Trichloroacetic acid | N/A | 80 | No loss |
pH <12.6 | N/A | N/A | No loss observed after 24 hrs. |
pH >12 | N/A | N/A | Irreversibly denatured |
pH 7-8 | 0.065-1.95 μg/mL | 4 | About 1 week |
pH 7-8 | 0.065-1.95 μg/mL | -20 | >6 months |
USAGE
Aprotinin is a competitive serine protease inhibitor which forms stable complexes with and blocks the active sites of enzymes. The binding is reversible, and most aprotinin-protease complexes dissociate at pH >10 or <3.
ENZYME - SOURCE - CONDITION INHIBITION | (Ki = Dissociation Constant) |
Acrosin | Weak inhibition |
Chymotrypsin | Ki = 9 nM |
Chymotrypsinogen (bovine), pH 8.0 | Ki = 9 nM |
CMP-N-Acetylneuraminate lactosylceramide a-2,3-sialyltransferase | 74% Inhibition at 300 nm |
Elastase (human leukocytes), pH 8.0 | Ki = 3.5 mM |
Kallikrein (pancreatic), pH 8.0 | Ki = 1.0 nM |
Kallikrein (plasma) | Ki = 30 nM; 100 nM |
Kallikrein (tissue) | Ki = 1 nM |
Kallikrein (urine) | Ki = 1.7 nM |
Plasmin (porcine), pH 7.8 | Ki = 4.0 nM |
Plasminogen activator | Ki = 8 mM; 27 mM |
Trypsin (bovine), pH 8.0 | Ki = 0.06 pM |
Trypsinogen (bovine), pH 8.0 | Ki = 1.8 mM |
Tryptase TL-2 | 16% Inhibition at 10 mM |
Urokinase (human), pH 8.8 | Ki = 8.0 mM |