Mitochondrial-morphology-targeted breeding of industrial yeast strains for alcohol fermentation

作者：Kitagaki Hiroshi^*

来源：Biotechnology and Applied Biochemistry, 2009, 53(3): 145-153.

DOI：10.1042/BA20090032

• alcohol fermentation
• industrial yeast breeding
• malic acid
• mitochondrial fragmentation
• mitochondrial morphology
• sake (Japanese rice wine)

Since mitochondrial genes are repressed under high glucose and low O(2), and these conditions correspond to the conditions in which yeast cells are exposed during alcohol fermentation, the existence and structure of yeast mitochondria during alcohol fermentation have not been elucidated. Yeast mitochondria can be observed throughout brewing of sake (Japanese rice wine) and fragment during brewing. Furthermore, it has been revealed that Fis I [fission I (mitochondrial outer membrane) homologue (Saccharomyces cerevisiae)], which is a transmembrane protein with its C-terminal anchor embedded in the outer membrane of mitochondria, is required for fragmentation of yeast mitochondria during sake brewing. By utilizing this knowledge, a fist disruptant of a sake yeast strain has been generated that has a networked mitochondrial structure throughout sake brewing. It transpired that this strain produces a high content of malate, which imparts a crisp acidic taste, during sake brewing. This strategy is a useful and a completely novel strategy towards developing a new yeast strain which produces a high content of malate in sake, and mitochondrial morphology has now emerged as a promising target for the breeding of practical industrial strains.

• 出版日期2009-7