罗氏原料11520857103

Cholesterol Esterase
from Pseudomonas species, lyophilizate 11 520 857 103
Hydrolase that splits fatty acids from sterols.
Application
Use Cholesterol Esterase in diagnostic tests for the determination of choles-
terol in combination with Cholesterol Oxidase, Catalog Nos. 10 634 522 103, 10
129 054103 or 11 479 709 103.
Benefits
Take advantage of the enhanced purity of this enzyme.
Rely on the proven diagnostic quality of this product.
EC 3.1.1.13
Properties
Nomenclature: Sterol-ester acylhydrolase
Molecular weight: ~129 kD
Isoelectric point: 4.5
Michaelis constant (Phosphate buffer, pH 7.5):
Cholesterol oleate: 7 x 10 -5 mol/l
Inhibitors: Heavy metals such as Cu 2+ , Ag + , Zn 2+
Activators: Detergents
pH optimum: 6.0-8.0; (maximum at pH 7.6) (see figure)
Temperature dependence: Not possible to determine under assay conditions
due to turbidity of Thesit at temperatures above +27°C.
pH stability: 6.0-6.5 (see figure)
Thermal stability: Below +20°C (see figure)
Specificity: Cholesterol esterase is an enzyme of lipid metabolism and gives
complete
cleavage of all serum cholesterol esters.
Remark: This Cholesterol esterase is especially suited for liquid stable ap-
plications with extended shelf life requirements.
Specification
Appearance: Brownish lyophilizate
Solubility: Clear, brown solution in water (c=50 mg/ml)
pH value (c=50 mg/ml in water): 7.0-8.0
Activity (+25°C, cholesterol oleate): ≥10 U/mg lyophilizate
Activity (+25°C, cholesterol oleate): ≥100 U/mg lyophilizate
Specific Activity: ≥100 U/mg protein
Protein (Biuret): No limit
Contaminants (expressed as percentage of Cholesterol Esterase activity):
ATPase: ≤0.005
Catalase: ≤1.00
Glycerokinase: ≤0.001
Glucose oxidase: ≤0.001
Hexokinase: ≤0.005
"NADH oxidase": ≤0.001
Uricase: ≤0.005
Stability: At +2 to +8°C within specification range for 12 months. Store dry.