El-Shora, H., Darwish, D., Taha, M. (2011). PURIFICATION, CHARACTERIZATION AND ACTIVE GROUPS OF BACTERIAL CHOLESTEROL OXIDASE.. Journal of Agricultural Chemistry and Biotechnology, 2(10), 205-215. doi: 10.21608/jacb.2011.57269
H. M. El-Shora; Doaa B. Darwish; Mai M. A. H. Taha. "PURIFICATION, CHARACTERIZATION AND ACTIVE GROUPS OF BACTERIAL CHOLESTEROL OXIDASE.". Journal of Agricultural Chemistry and Biotechnology, 2, 10, 2011, 205-215. doi: 10.21608/jacb.2011.57269
El-Shora, H., Darwish, D., Taha, M. (2011). 'PURIFICATION, CHARACTERIZATION AND ACTIVE GROUPS OF BACTERIAL CHOLESTEROL OXIDASE.', Journal of Agricultural Chemistry and Biotechnology, 2(10), pp. 205-215. doi: 10.21608/jacb.2011.57269
El-Shora, H., Darwish, D., Taha, M. PURIFICATION, CHARACTERIZATION AND ACTIVE GROUPS OF BACTERIAL CHOLESTEROL OXIDASE.. Journal of Agricultural Chemistry and Biotechnology, 2011; 2(10): 205-215. doi: 10.21608/jacb.2011.57269
PURIFICATION, CHARACTERIZATION AND ACTIVE GROUPS OF BACTERIAL CHOLESTEROL OXIDASE.
Botany Dept., Faculty of Science, Mans. Univ., Mansoura, Egypt.
Abstract
Cholesterol oxidase (EC 1.1.3.6) was isolated and purified from Staphylococcus epidermidis. The enzyme was purified with 60% ammonium sulphate followed by DEAE-Cellulose and Sephadex-200. The specific activity was 62 U mg-1 protein and the purification fold was 43.4. The optimum temperature was 40ºC and the optimum pH was 8.0. The Km for cholesterol was 0.33 mM and for CaCl2 was 0.23mM. The enzyme was inhibited by phenyl mercuric acetate (PMA), N-acetylimidazole (NAI), diethylpyrocarbonate (DEPC) and phenyl glyoxal (PG) indicating the presence of sulphhydryl, tyrosyl, histidyl and arginyl groups. The enzyme was activated by Ca2+ at 1.0 and 5.0 mM. Also Mn2+, Mg2+ and K+ were activators. Ba2+ and Zn2+ were inhibitors at the higher concentrations, whereas Al3+ and Cu 2+ were inhibitors at lower and higher concentrations.