Open AccessImproved sake metabolic profile during fermentation due to increased mitochondrial pyruvate dissimilation
Author(s) -
Agrimi Gennaro,
Mena Maria C.,
Izumi Kazuki,
Pisano Isabella,
Germinario Lucrezia,
Fukuzaki Hisashi,
Palmieri Luigi,
Blank Lars M.,
Kitagaki Hiroshi
Publication year - 2014
Publication title -
fems yeast research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.991
H-Index - 92
eISSN - 1567-1364
pISSN - 1567-1356
DOI - 10.1111/1567-1364.12120
Subject(s) - pyruvate dehydrogenase complex , fermentation , yeast , pyruvate decarboxylation , biochemistry , mitochondrion , biology , pyruvate dehydrogenase kinase , glycerol , pyruvate decarboxylase , anaerobic exercise , metabolism , flux (metallurgy) , pyruvic acid , chemistry , alcohol dehydrogenase , enzyme , physiology , organic chemistry
Although the decrease in pyruvate secretion by brewer's yeasts during fermentation has long been desired in the alcohol beverage industry, rather little is known about the regulation of pyruvate accumulation. In former studies, we developed a pyruvate under‐secreting sake yeast by isolating a strain ( TCR 7) tolerant to ethyl α‐transcyanocinnamate, an inhibitor of pyruvate transport into mitochondria. To obtain insights into pyruvate metabolism, in this study, we investigated the mitochondrial activity of TCR 7 by oxigraphy and 13 C‐metabolic flux analysis during aerobic growth. While mitochondrial pyruvate oxidation was higher, glycerol production was decreased in TCR 7 compared with the reference. These results indicate that mitochondrial activity is elevated in the TCR 7 strain with the consequence of decreased pyruvate accumulation. Surprisingly, mitochondrial activity is much higher in the sake yeast compared with CEN . PK 113‐7 D , the reference strain in metabolic engineering. When shifted from aerobic to anaerobic conditions, sake yeast retains a branched mitochondrial structure for a longer time than laboratory strains. The regulation of mitochondrial activity can become a completely novel approach to manipulate the metabolic profile during fermentation of brewer's yeasts.