Cunha Anderson F, Missawa Silvia K, Gomes Luiz H, Reis Sérgio F, Pereira Gonçalo A G
Laboratório de Genômica e Expressão, Departamento de Genética e Evolução Instituto de Biologia, Universidade Estadual de Campinas, São Paulo, Brazil.
FEMS Yeast Res. 2006 Mar;6(2):280-7. doi: 10.1111/j.1567-1364.2006.00038.x.
The goal of this study was to develop conditional flocculant yeasts for use in the alcohol fermentation industry. Promoters were constructed to completely repress gene transcription in the presence of sugar and to support strong expression after the exhaustion of this compound. A fusion of regulatory regions of the ADH2 promoter with the FLO5 core promoter was constructed to regulate the FLO5 gene. This construct was inserted into multicopy plasmids and transformed into laboratory strains of Saccharomyces cerevisiae, whereby the transformed cells were selected by sedimentation from the bulk medium after sugar exhaustion, without decreasing ethanol production. The ADH2-FLO5 region was converted into an integrative cassette to disrupt the CAN1 gene in industrial yeast strains. Transformed cells became resistant to canavanine and demonstrated conditional flocculation. Although ethanol production was significantly decreased in the industrial transformants, this development reveals a promising technology for the substitution of centrifugation in industrial ethanol production.
本研究的目标是开发用于酒精发酵工业的条件性絮凝酵母。构建启动子，使其在有糖存在时完全抑制基因转录，并在该化合物耗尽后支持强表达。构建了ADH2启动子调控区与FLO5核心启动子的融合体来调控FLO5基因。将该构建体插入多拷贝质粒并转化到酿酒酵母实验室菌株中，糖耗尽后通过从大量培养基中沉降来选择转化细胞，且不降低乙醇产量。将ADH2-FLO5区域转化为整合盒以破坏工业酵母菌株中的CAN1基因。转化细胞对刀豆氨酸产生抗性并表现出条件性絮凝。尽管工业转化体中的乙醇产量显著降低，但这一进展揭示了一种有望在工业乙醇生产中替代离心的技术。
