Effects of culture conditions on ergosterol biosynthesis by Saccharomyces cerevisiae.
Ergosterol is an essential component of yeast cells that maintains the integrity of the membrane. It was investigated as an important factor in the ethanol tolerance of yeast cells. We investigated the effects of brewing conditions on the ergosterol contents of S. cerevisiae K-9, sake yeast, several kinds of Saccharomyces cerevisiae that produce more than 20% ethanol, and X2180-1A, laboratory yeast. K-9 had a higher total ergosterol contents under all the conditions we examined than X2180-1A. Ethanol and hypoxia were found to have negative and synergistic effects on the total ergosterol contents of both strains, and significantly reduced the free ergosterol contents of X2180-1A but only slightly reduced those of K-9. The maintenance of free ergosterol contents under brewing conditions might be an important character of sake yeast strains. DNA microarray analysis also showed higher expression of ergosterol biosynthesis genes in K-9 than in X2180-1A.
Shobayashi
Megumi
M
National Research Institute of Brewing, Hiroshima, Japan.
Mitsueda
Shin-ichiro
S
Ago
Mariko
M
Fujii
Tsutomu
T
Iwashita
Kazuhiro
K
Iefuji
Haruyuki
H
D000434:Alcoholic Beverages; D002492:Central Nervous System Depressants / Q000494:pharmacology; D003470:Culture Media; D004271:DNA, Fungal / Q000096:biosynthesis / Q000235:genetics; D004875:Ergosterol / Q000096:biosynthesis*; D000431:Ethanol / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D010100:Oxygen / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*
D002492:Central Nervous System Depressants; D003470:Culture Media; D004271:DNA, Fungal; D000431:Ethanol; D010100:Oxygen; D004875:Ergosterol