Engineering of a novel Saccharomyces cerevisiae wine strain with a respiratory phenotype at high external glucose concentrations
Artikel i vetenskaplig tidskrift, 2005

The recently described respiratory strain Saccharomyces cerevisiae KOY.TM6*P is, to our knowledge, the only reported strain of S. cerevisiae which completely redirects the flux of glucose from ethanol fermentation to respiration, even at high external glucose concentrations (27). In the KOY.TM6*P strain, portions of the genes encoding the predominant hexose transporter proteins, Hxt1 and Hxt7, were fused within the regions encoding transmembrane (TM) domain 6. The resulting chimeric gene, TM6*, encoded a chimera composed of the amino-terminal half of Hxt1 and the carboxy-terminal half of Hxt7. It was subsequently integrated into the genome of an hxt null strain. In this study, we have demonstrated the transferability of this respiratory phenotype to the V5 hxt1-7 strain, a derivative of a strain used in enology. We also show by using this mutant that it is not necessary to transform a complete hxt null strain with the TM6* construct to obtain a nonethanol- producing phenotype. The resulting V5.TM6*P strain, obtained by transformation of the V5 hxt1-7 strain with the TM6* chimeric gene, produced only minor amounts of ethanol when cultured on external glucose concentrations as high as 5%. Despite the fact that glucose flux was reduced to 30% in the V5.TM6*P strain compared with that of its parental strain, the V5.TM6*P strain produced biomass at a specific rate as high as 85% that of the V5 wild-type strain. Even more relevant for the potential use of such a strain for the production of heterologous proteins and also of low-alcohol beverages is the observation that the biomass yield increased 50% with the mutant compared to its parental strain.

yeast

individual hexose transporters

pyruvate-kinase

hxt genes

repression

glycolytic-enzymes

growth

chemostat cultures

fermentative capacity

hexokinase-pii

Författare

Cecilia Henricsson

Chalmers, Kemi- och bioteknik, Molekylär bioteknik

Maria de Jesus-Ferreira

Université de Montpellier

Kristina Hedfalk

Göteborgs universitet

Karin Elbing

Chalmers

University of Pittsburgh School of Medicine

Christer Larsson

Chalmers, Kemi- och bioteknik, Molekylär bioteknik

Joakim Norbeck

Chalmers, Kemi- och bioteknik, Molekylär bioteknik

Roslyn Bill

Chalmers

Stefan Hohmann

Göteborgs universitet

Lena Gustafsson

Chalmers, Kemi- och bioteknik, Molekylär bioteknik

Applied and Environmental Microbiology

0099-2240 (ISSN) 1098-5336 (eISSN)

Vol. 71 10 6185-6192

Ämneskategorier

Mikrobiologi

DOI

10.1128/AEM.71.10.6185-6192.2005

PubMed

16204537

Mer information

Senast uppdaterat

2018-09-10