Premium
Construction of self‐cloning industrial brewing yeast with high‐glutathione and low‐diacetyl production
Author(s) -
Wang ZhaoYue,
He XiuPing,
Liu Nan,
Zhang BoRun
Publication year - 2008
Publication title -
international journal of food science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.831
H-Index - 96
eISSN - 1365-2621
pISSN - 0950-5423
DOI - 10.1111/j.1365-2621.2007.01546.x
Subject(s) - brewing , fermentation , yeast , glutathione , cloning (programming) , biology , saccharomyces cerevisiae , diacetyl , biochemistry , molecular cloning , industrial microbiology , heterologous expression , gene , food science , recombinant dna , gene expression , enzyme , computer science , programming language
Summary Self‐cloning strains of industrial brewing yeast were constructed, in which one allele of α‐acetohydroxyacid synthase (AHAS) gene ( ILV2 ) was disrupted by integrating Saccharomyces cerevisiae genes, γ‐glutamylcysteine synthetase gene ( GSH1 ) and copper resistant gene ( CUP1 ) into the locus of ILV2 . The self‐cloning strains were selected for their resistance to CuSO 4 and identified by PCR amplification. The results of AHAS and glutathione (GSH) assay from fermentation with the self‐cloning strains in 500‐mL conical flask showed that AHAS activity decreased and GSH content increased compared with that of host yeasts. The results of pilot scale brewing in 5‐L fermentation tank also indicated that GSH content in beer fermented with self‐cloning strains T5‐3 and T31‐2 was 1.3 fold and 1.5 fold of that of host QY5 and QY31, respectively; and diacetyl content decreased to 64% and 58% of their hosts, respectively. The self‐cloning strains do not contain any heterologous DNA, they may be more acceptable to the public.