摘要
【目的】研究在不同浓度2-苯乙醇作用下,酵母生理生化特性的变化规律,为优化2-苯乙醇生物合成过程提供重要依据。【方法】透射电镜观察细胞形态;流式细胞术检测细胞膜渗透性、胞内ROS浓度、线粒体膜电位;实时荧光定量PCR检测关键酶基因表达。【结果】随着2-苯乙醇浓度增加(从0到4.0 g/L),酵母细胞分解代谢能力、细胞膜渗透性及aro10基因表达量逐渐降低;线粒体膜电位逐渐增加;胞内ROS浓度先增加后减少。当2-苯乙醇浓度从2.4 g/L增加到3.0 g/L,酵母的分解代谢能力、细胞膜渗透性、aro10基因表达水平等生理生化特性都发生较为显著的变化。【结论】产物原位转移过程中水相2-苯乙醇浓度可考虑控制在2.4 3.0 g/L。
[Objective] To provide useful basis for enhancing the biosynthesis of 2-phenylethanol （PEA）, we studied the variation of physiological and biochemical characteris- tics of Saccharomyces cerevisiae sp. strain R-UV3 treated on varied concentrations of PEA.[Methods] Morphological observation was performed by a transmission electron microscope. Membrane permeabilization, intracellular reactive oxygen species （ROS） and mitochondrial membrane potential after staining with propidium iodide, dihydroethidium and rhodamine 123 respectively were investigated at the single-cell level with flow cytometry. The expression of arolO gene was determined by real-time fluorescence quantitative PCR. ]Results] With the increasing PEA concentration （0-4.0 g/L）, the membrane permeabilization, glycometabolism and expression of arolO gene in the yeast cell decreased and mitochondrial membrane poten- tial increased. ROS increased when PEA concentration was below 3.0 g/L and decreased when PEA concentration was beyond 3.0 g/L. The physiological and biochemical characteristics of the yeast, such as membrane permeabilization, glycometabolism and expression of arolO gene, varied notably as PEA concentration increased from 2.4 g/L to 3.0 g/L. [Conclusions[ The aqueous PEA concentration should be controlled at 2.4-3.0 g/L when in situ PEA removal technology was performed.
出处
《微生物学通报》
CAS
CSCD
北大核心
2012年第6期749-755,共7页
Microbiology China
基金
福州大学科研启动基金项目(No.0460022445)
关键词
2-苯乙醇
酿酒酵母
生理生化特性
流式细胞术
2-phenylethanol, Saccharomyces cerevisiae, Physiological and biochemical character-istic, Flow cytometry
