The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates
| ISSN: |
0006-291X
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|---|---|
| Source: |
Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
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| Topics: |
Biology
Chemistry and Pharmacology
Physics
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| Type of Medium: |
Electronic Resource
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| URL: |
| _version_ | 1798292254065950721 |
|---|---|
| autor | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. |
| autorsonst | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. |
| book_url | http://dx.doi.org/10.1016/0006-291X(78)90593-4 |
| datenlieferant | nat_lic_papers |
| fussnote | Electrofocusing of a highly-purified preparation of bovine adrenocortical cytochrome P-450(scc) showed a single peak of enzyme activity at pH 6.8, when either cholesterol, [20S]-20-hydroxycholesterol, [22R]-22-hydroxycholesterol or [20R, 22R]-20, 22-dihydroxycholesterol was used as the substrate for the side chain cleavage reaction. The formation of pregnenolone from these hydroxycholesterols was inhibited by [20R, 22S]-20, 22-epoxycholesterol similarly in a competitive manner and the Ki value for the epoxide was found to be 12-15 μM for all these substrates. When one of the above mentioned substrates was incubated in a concentration sufficient for maximal reaction velocity, the addition of another hydroxycholesterol did not result in further increase of pregnenolone production. These results support the assumption that a single species of enzyme catalyzes all the three steps of the reaction, i.e., 20-hydroxylation, 22-hydroxylation and cleavage of carbon chain between carbon-20 and carbon-22. |
| hauptsatz | hsatz_simple |
| identnr | NLZ184234875 |
| issn | 0006-291X |
| journal_name | Biochemical and Biophysical Research Communications |
| materialart | 1 |
| package_name | Elsevier |
| publikationsort | Amsterdam |
| publisher | Elsevier |
| reference | 82 (1978), S. 179-187 |
| search_space | articles |
| shingle_author_1 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. |
| shingle_author_2 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. |
| shingle_author_3 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. |
| shingle_author_4 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. |
| shingle_catch_all_1 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates 0006-291X 0006291X Elsevier |
| shingle_catch_all_2 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates 0006-291X 0006291X Elsevier |
| shingle_catch_all_3 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates 0006-291X 0006291X Elsevier |
| shingle_catch_all_4 | Duque, C. Morisaki, M. Ikekawa, N. Shikita, M. The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates 0006-291X 0006291X Elsevier |
| shingle_title_1 | The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates |
| shingle_title_2 | The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates |
| shingle_title_3 | The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates |
| shingle_title_4 | The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates |
| sigel_instance_filter | dkfz geomar wilbert ipn albert fhp |
| source_archive | Elsevier Journal Backfiles on ScienceDirect 1907 - 2002 |
| timestamp | 2024-05-06T08:45:35.793Z |
| titel | The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates |
| titel_suche | The enzyme activity of bovine adrenocortical cytochrome P-450 producing pregnenolone from cholesterol: Kinetic and electrophoretic studies on the reactivity of hydroxycholesterol intermediates Electrofocusing of a highly-purified preparation of bovine adrenocortical cytochrome P-450(scc) showed a single peak of enzyme activity at pH 6.8, when either cholesterol, [20S]-20-hydroxycholesterol, [22R]-22-hydroxycholesterol or [20R, 22R]-20, 22-dihydroxycholesterol was used as the substrate for the side chain cleavage reaction. The formation of pregnenolone from these hydroxycholesterols was inhibited by [20R, 22S]-20, 22-epoxycholesterol similarly in a competitive manner and the Ki value for the epoxide was found to be 12-15 μM for all these substrates. When one of the above mentioned substrates was incubated in a concentration sufficient for maximal reaction velocity, the addition of another hydroxycholesterol did not result in further increase of pregnenolone production. These results support the assumption that a single species of enzyme catalyzes all the three steps of the reaction, i.e., 20-hydroxylation, 22-hydroxylation and cleavage of carbon chain between carbon-20 and carbon-22. |
| topic | W V U |
| uid | nat_lic_papers_NLZ184234875 |