Interruption of glycerol pathway in industrial alcoholic yeasts to improve the ethanol production.
The two homologous genes GPD1 and GPD2, encoding two isoenzymes of NAD(+)-dependent glycerol-3-phosphate dehydrogenase in industrial yeast Saccharomyces cerevisiae CICIMY0086, had been deleted. The obtained two kinds of mutants gpd1Delta and gpd2Delta were studied under alcoholic fermentation conditions. gpd1Delta mutants exhibited a 4.29% (relative to the amount of substrate consumed) decrease in glycerol production and 6.83% (relative to the amount of substrate consumed) increased ethanol yield while gpd2Delta mutants exhibited a 7.95% (relative to the amount of substrate consumed) decrease in glycerol production and 7.41% (relative to the amount of substrate consumed) increased ethanol yield compared with the parental strain. The growth rate of the two mutants were slightly lower than that of the wild type under the exponential phase whereas ANG1 (gpd1Delta) and the decrease in glycerol production was not accompanied by any decline in the protein content of the strain ANG1 (gpd1Delta) but a slight decrease in the strain ANG2 (gpd2Delta). Meanwhile, dramatic decrease of acetate acid formation was observed in strain ANG1 (gpd1Delta) and ANG2 (gpd2Delta) compared to the parental strain. Therefore, it is possible to improve the ethanol yield by interruption of glycerol pathway in industrial alcoholic yeast.
Guo
Zhong-peng
ZP
The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China.
Zhang
Liang
L
Ding
Zhong-yang
ZY
Wang
Zheng-Xiang
ZX
Shi
Gui-Yang
GY
D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005990:Glycerol / Q000378:metabolism*; D050536:Glycerol-3-Phosphate Dehydrogenase (NAD+) / Q000235:genetics* / Q000378:metabolism; D007218:Industrial Microbiology; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D017384:Sequence Deletion
D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; D050536:Glycerol-3-Phosphate Dehydrogenase (NAD+); D005990:Glycerol