| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject esterase capable of hydrolyzing an ester type cholesterol and having physicochemical properties useful for the diagnosis of arteriosclerosis and myocardial infarct and excellent in practical properties by culturing a specific strain belonging to the genus Burkholderia. SOLUTION: This cholesterol esterase is obtained by culturing strains of Burkholderia-sp. No.120-11 (FERM-P-15924), etc., and has the following properties: (1) hydrolyses a cholesterol ester to form a fatty acid and cholesterol; (2) affects cholesterol linoleate most strongly, affects cholesterol oleate, cholesterol palmitate and cholesterol octanoate, and only scarcely affects cholesterol acetate, etc.; (3) an optimum pH is in the vicinity of 6.5, suitable temperature range for action thereof is 43-47 deg.C, stable up to approximately 60 deg.C and excellent in thermal stability. |
