Construction of lactose-assimilating and high-ethanol-producing yeasts by protoplast fusion

Journal Article · Sat Feb 01 00:00:00 EST 1986 · Appl. Environ. Microbiol.; (United States)

OSTI ID:6231219

Farahnak, F; Seki, T; Ryu, D D.Y.; Ogrydziak, D

The availability of a yeast strain which is capable of fermenting lactose and at the same time is tolerant to high concentrations of ethanol would be useful for the production of ethanol from lactose. Kluyveromyces fragilis is capable of fermenting lactose, but it is not as tolerant as Saccharomyces cerevisiae to high concentrations of ethanol. In this study, the authors have used the protoplast fusion technique to construct hybrids between auxotrophic strains of S. cerevisiae having high ethanol tolerance and an auxotrophic strain of lactose-fermenting K. fragilis isolated by ethyl methanesulfonate mutagenesis. The fusants obtained were prototrophic and capable of assimilating lactose and producing ethanol in excess of 13% (vol/vol). The complementation frequency of fusion was about 0.7%. Formation of fusants was confirmed by the increased amount of chromosomal DNA per cell. Fusants contained 8 x 10/sup -9/ to 16 x 10/sup -8/ ..mu..g of DNA per cell as compared with about 4 x 10/sup -8/ ..mu..g of DNA per cell for the parental strains, suggesting that multiple fusions had taken place.

• Research Organization: Univ. of California, Davis
• OSTI ID: 6231219
• Journal Information: Appl. Environ. Microbiol.; (United States), Vol. 51:2
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
ETHANOL
YIELDS
LACTOSE
FERMENTATION
YEASTS
HYBRIDIZATION
DNA
GENETICS
PLANT CELLS
SACCHAROMYCES CEREVISIAE
ALCOHOLS
BIOCONVERSION
BIOLOGY
CARBOHYDRATES
DISACCHARIDES
FUNGI
HYDROXY COMPOUNDS
MICROORGANISMS
NUCLEIC ACIDS
OLIGOSACCHARIDES
ORGANIC COMPOUNDS
PLANTS
SACCHARIDES
SACCHAROMYCES
090222* - Alcohol Fuels- Preparation from Wastes or Biomass- (1976-1989)