Chromosomal location of Lg-FLO1 in bottom-fermenting yeast and the FLO5 locus of industrial yeast.
OBJECTIVE
To determine the chromosomal location and entire sequence of Lg-FLO1, the expression of which causes the flocculation of bottom-fermenting yeast.


RESULTS
Two cosmid clones carrying DNA from a bottom-fermenting yeast chromosome VIII right-arm end were selected by colony hybridization. Sequencing revealed that the clones contained DNA derived from a Saccharomyces cerevisiae type chromosome VIII and a Saccharomyces bayanus type chromosome VIII, both from bottom-fermenting yeast.


CONCLUSIONS
Lg-FLO1 is located on the S. cerevisiae type chromosome VIII at the same position as the FLO5 gene of the laboratory yeast S. cerevisiae S288c. The unique chromosome VIII structure of bottom-fermenting yeast is conserved among other related strains. FLO5 and Lg-FLO1 promoter sequences are identical except for the presence of three 42 bp repeats in the latter, which are associated with gene activity. Flocculin genes might have been generated by chromosomal recombination at these repeats.


CONCLUSIONS
This is the first report of the exact chromosomal location and entire sequence of Lg-FLO1. This information will be useful in the brewing industry for the identification of normal bottom-fermenting yeast. Moreover, variations in the FLO5 locus among strains are thought to reflect yeast evolution.
Brewing Research & Development Laboratory, Asahi Breweries Ltd., Ibaraki, Japan. tomoo.ogata@asahibeer.co.jp
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Ogata
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Izumikawa
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Kohno
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Shibata
D001483:Base Sequence; D001515:Beer; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D005427:Flocculation; D005800:Genes, Fungal; D007218:Industrial Microbiology; D037241:Mannose-Binding Lectins; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017385:Sequence Homology
D017931:DNA Primers; C087578:FLO1 protein, S cerevisiae; D037241:Mannose-Binding Lectins; D029701:Saccharomyces cerevisiae Proteins