Identification of bottom-fermenting yeast genes expressed during lager beer fermentation.
It has been proposed that bottom-fermenting yeast strains of Saccharomyces pastorianus possess at least two types of genomes. Sequences of genes of one genome [S. cerevisiae (Sc)-type] have been found to be highly homologous (more than 90% identity) to S. cerevisiae S288C sequences, while those of the other [Lager (Lg)-type] are less so. To identify and discriminate Lg-type from Sc-type genes expressed during lager beer fermentation, normalized cDNA libraries were constructed and analysed. From approximately 22 000 ESTs, 3892 Sc-type and 2695 Lg-type ORFs were identified. Expression patterns of Sc- and Lg-type genes did not correlate with particular cell functions in KEGG classification system. Moreover, 405 independent clones were isolated that have no significant homology with sequences in the S288C database, suggesting that they include the bottom-fermenting yeast-specific (BFY) genes. Most of BFY genes have significant homology with the S. bayanus genome.
Yoshida
Satoshi
S
Central Laboratories for Frontier Technology, Kirin Brewery Co. Ltd, Kanagawa, Japan. satoshiy@kirin.co.jp
Hashimoto
Kaori
K
Shimada
Emiko
E
Ishiguro
Tatsuji
T
Minato
Toshiko
T
Mizutani
Satoru
S
Yoshimoto
Hiroyuki
H
Tashiro
Kosuke
K
Kuhara
Satoru
S
Kobayashi
Osamu
O
D001515:Beer / Q000382:microbiology*; D002874:Chromosome Mapping; D004271:DNA, Fungal / Q000737:chemistry; D020224:Expressed Sequence Tags; D005285:Fermentation; D020869:Gene Expression Profiling; D015723:Gene Library; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D012440:Saccharomyces / Q000235:genetics*; D017422:Sequence Analysis, DNA
D004271:DNA, Fungal