海藻糖的生物学机制在酿酒活性干酵母(AADY)中的应用

THE BIOCHEMICAL MECHANISM OF TREHALOSE AND ITS APPLICATION IN AADY

α,α-海藻糖是典型的应激代谢物,具有在极端环境下能发生复杂的生物应激合成代谢机制,进行胁迫保护等独特的生物学特性,能特异性地稳定生物大分子结构,而酿酒活性干酵母(Alcohol-fermentionActiveDryYeast,AADY)生产的关键是增强酿酒酵母的抗逆性,细胞内海藻糖的含量是鉴定AADY质量和活性的一个重要指标,海藻糖含量较高的AADY其存活率明显高于低海藻糖含量的AADY。对海藻糖生物学特性的研究,为综合利用现代生物技术、真空冷冻干燥和流化床干燥等高新技术手段,生产高品质AADY提供了一种有效的途径,并为AADY抗逆性基因工程的深入研究提供了一种新的思路。

Trehalose （α-D-glucopyranosyl-[1,1]-α-D-glucopyranoside） is a non-reducing disaccharide sugar that is made up of two glucose units joined by an α,α-1,1 linkage and is common in nature. As a typical stress metabolites with complex biosynthesis and metabolism mechanism under a variety of stress conditions, including heat-shock, hydrostatic pressure, desiccation, nutrient starvation osmotic or oxidative stress, and exposure to toxicants, trehalose has special physiological hallmark which has been recognized as a crucial stress resistance mechanism that stabilizes proteins and biological membranes. The intracellular content of trehalose is an important indicator of quality of AADY. Normally found in Saccharomyces cerevisiae and other organisms only as traces of trehalose, such as content of 2 %-3 %（w/w）, it can noticeably enhance viability of ceils. In yeast submitted to stress conditions, the intracellular concentration of trehalose can reach up to 35 %（w/w） which can effectively decrease loss of fermentation vitality and damage of ceils when desiccating phase of water content of 5 %- 10 % in yeast. The exogenesis α,α-Trehalose has similar function, Because the key of manufacture of AADY is to buildup stress resistance of Saccharomyces cerevisiae, the research of metabolism and regulation mechanisms, the exploration of stress resilience mechanisms at the molecular level and the establishment of the modern analytical methods of trehalose which benefit to break through this bottleneck of continuous development of AADY industry through utilizing comprehensive modern high-technology including bioengineering, vacuum freezedrying and the fluid-bed drying and so on, Moreover, they will inspire novel mentality to profoundly explore and develop resistance gene of AADY.