Oxygen requirements for formation and activity of the squalene epoxidase in Saccharomyces cerevisiae.

摘要: The effect of oxygen on squalene epoxidase activity in Saccharomyces cerevisiae was investigated. In cells grown standing cultures, the localized mainly "mitochondrial" fraction. Upon aeration, enzyme increased and newly formed associated with "microsomal" At 0.03% (vol/vol) oxygen, levels doubled, whereas ergosterol level only slightly increased. Cycloheximide inhibited increase under these conditions. An apparent Km for 0.38% determined from a crude particulate preparation epoxidase.