| Abstract: | ERG3 is the structural gene in Saccharomyces cerevisiae for the sterol Δ5 desaturase that introduces the C5=6 unsaturation in ergosterol biosynthesis. The ERG3 gene has been mapped on chromosome XII, 13·7 centimorgans from GAL2 toward SPT8. The essentially of the gene is dependent on the conditions used for the cultivation of the mutants. Insertionally inactivated mutants of ERG3 fail to grow without ‘sparking’ levels of Δ5 sterols in heme-deficient cells, and are unable to grow on the respiratory substrates glycerol and ethanol. |
