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Two moles of O2 consumption and one mole of H2O2 formation during cholesterol peroxidation with cholesterol oxidase from Pseudomonas sp. strain ST-200.

ABSTRACT: Cholesterol oxidase from Pseudomonas sp. strain ST-200 oxidized cholesterol and cholestanol to 6beta-hydroperoxycholest-4-en-3-one and 5alpha-cholestan-3-one respectively. The former was converted spontaneously to several oxysteroids such as 6-hydroxycholest-4-en-3-one and cholest-4-ene-3,6-dione, with the consumption of 2 mol of O(2) and the formation of 1 mol of H(2)O(2) for each mole of cholesterol oxidized. An oxidized form of the cholesterol oxidase dehydrogenates cholesterol, probably to the 5-en-3-one derivative. A reduced form of the enzyme, yielded from the cholesterol dehydrogenation reaction, dioxygenated cholest-5-en-3-one to 6beta-hydroperoxycholest-4-en-3-one.

SUBMITTER: Doukyu N

PROVIDER: S-EPMC1220399 | biostudies-other | 1999 Aug

REPOSITORIES: biostudies-other

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