Preparation of 14C-labeled and unlabeled sterol intermediates from yeast using metabolic inhibitors.
The method for the preparation of zymosterol was improved (13 mg of zymosterol/g dry cells) by the aerobic adaptation of the cells in the presence of 1 mM DL-ethionine. Lanosterol was also found to accumulate (5.0 mg/g dry cells) when the cells were adapted aerobically in the presence of 10(-4) M buthiobate. Pure lanosterol could be obtained by separation of the unsaponifiable lipids on TLC. Pure [14C]lanosterol with a high specific radioactivity (56 Ci/mol) could be prepared by incubation of the desiccated cells with [14C]isopentenyl pyrophosphate, cofactors such as ATP and NADPH-generating system, and buthiobate in phosphate buffer. The method using desiccated cells may also be applicable to the preparation of other radioactive sterol intermediates.
D000693:Anaerobiosis; D002784:Cholesterol; D005001:Ethionine / Q000494:pharmacology; D045782:Hemiterpenes; D007810:Lanosterol / Q000378:metabolism*; D008798:Mevalonic Acid / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*; D013261:Sterols / Q000378:metabolism*
D045782:Hemiterpenes; D009943:Organophosphorus Compounds; D013261:Sterols; D007810:Lanosterol; C004809:isopentenyl pyrophosphate; D002784:Cholesterol; C015582:zymosterol; D008798:Mevalonic Acid; D005001:Ethionine