Affiliation:
1. National Research Institute of Brewing, 3-7-1, Kagamiyama, Higashihiroshima 739-0046, Japan
Abstract
ABSTRACT
Sake, a traditional alcoholic beverage in Japan, is brewed with sake yeasts, which are classified as
Saccharomyces cerevisiae
. Almost all sake yeasts form a thick foam layer on sake mash during the fermentation process because of their cell surface hydrophobicity, which increases the cells' affinity for bubbles. To reduce the amount of foam, nonfoaming mutants were bred from foaming sake yeasts. Nonfoaming mutants have hydrophilic cell surfaces and no affinity for bubbles. We have cloned a gene from a foam-forming sake yeast that confers foaming ability to a nonfoaming mutant. This gene was named
AWA1
and structures of the gene and its product were analyzed. The N- and C-terminal regions of Awa1p have the characteristic sequences of a glycosylphosphatidylinositol anchor protein. The entire protein is rich in serine and threonine residues and has a lot of repetitive sequences. These results suggest that Awa1p is localized in the cell wall. This was confirmed by immunofluorescence microscopy and Western blotting analysis using hemagglutinin-tagged Awa1p. Moreover, an
awa1
disruptant of sake yeast was hydrophilic and showed a nonfoaming phenotype in sake mash. We conclude that Awa1p is a cell wall protein and is required for the foam-forming phenotype and the cell surface hydrophobicity of sake yeast.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology
Reference32 articles.
1. Adams A. D. E. Gottschling C. Kaiser and T. Stearns. 1997. Methods in yeast genetics. Cold Spring Harbor Laboratory Press New York N.Y.
2. Akiyama-Jibiki, M., T. Ishibiki, H. Yamashita, and M. Eto. 1997. A rapid and simple assay to measure flocculation in brewer's yeast. Master Brewers Assoc. Am. Tech. Q.34:278-281.
3. Ausubel F. M. R. Brent R. E. Kingston and D. D. Moore. 1999. Short protocols in molecular biology. John Wiley & Sons New York N.Y.
4. Becker, D. M., and L. Guarente. 1991. High-efficiency transformation of yeast by electroporation. Methods Enzymol.194:182-187.
5. Burns, N., B. Grimwade, P. B. Ross-Macdonald, E. Y. Choi, K. Finberg, G. S. Roeder, and M. Snyder. 1994. Large-scale analysis of gene expression, protein localization, and gene disruption in Saccharomyces cerevisiae.Genes Dev.8:1087-1105.
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