Molecular and physiological aspects of alcohol dehydrogenases in the ethanol metabolism of Saccharomyces cerevisiae
Molecular and physiological aspects of alcohol dehydrogenases in the ethanol metabolism of Saccharomyces cerevisiae
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DOI：
10.1111/j.1567-1364.2011.00760.x
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发表时间：
2012-02-01
影响因子：
3.2
通讯作者：
Albertyn, Jacobus
中科院分区：
文献类型：
--
作者：
de Smidt, Olga;du Preez, James C.;Albertyn, Jacobus
对酿酒酵母中5种乙醇脱氢酶(ADH)同工酶Q1Q5的四倍缺失突变株的生理功能和功能替代进行了研究。它们在好氧分批培养中的生长是根据动力学和化学计量参数来表征的。以葡萄糖或乙醇为碳源的培养表明，Adh1是唯一能有效催化乙醛还原为乙醇的乙醇脱氢酶。产生的或添加的乙醇的氧化也可以归因于Adh1。缺乏ADH1基因的菌株的生长导致作为主要发酵产物的甘油的产生，同时伴随着大量乙醛的产生。菌株Q2和Q3分别只表达ADH2和ADH3，它们从葡萄糖中生产乙醇，尽管比菌株Q1少，而且也能够氧化添加的乙醇。菌株Q4和Q5在葡萄糖上生长不良，并产生乙醇，但既不能利用产生的乙醇，也不能在添加乙醇的情况下生长。ADH4和ADH5基因的转录图谱表明，这些基因产物不太可能参与葡萄糖生产乙醇的过程。
The physiological role and possible functional substitution of each of the five alcohol dehydrogenase (Adh) isozymes in Saccharomyces cerevisiae were investigated in five quadruple deletion mutants designated strains Q1Q5, with the number indicating the sole intact ADH gene. Their growth in aerobic batch cultures was characterised in terms of kinetic and stoichiometric parameters. Cultivation with glucose or ethanol as carbon substrate revealed that Adh1 was the only alcohol dehydrogenase capable of efficiently catalysing the reduction of acetaldehyde to ethanol. The oxidation of produced or added ethanol could also be attributed to Adh1. Growth of strains lacking the ADH1 gene resulted in the production of glycerol as a major fermentation product, concomitant with the production of a significant amount of acetaldehyde. Strains Q2 and Q3, expressing only ADH2 or ADH3, respectively, produced ethanol from glucose, albeit less than strain Q1, and were also able to oxidise added ethanol. Strains Q4 and Q5 grew poorly on glucose and produced ethanol, but were neither able to utilise the produced ethanol nor grow on added ethanol. Transcription profiles of the ADH4 and ADH5 genes suggested that participation of these gene products in ethanol production from glucose was unlikely.