糖诱导型启动子调控ALD6基因表达降低黄酒中的高级醇生成量  

Regulating ALD6 gene expression by sugar-inducible promoter to reduce the production of higher alcohols in rice wine

作　　者：康新玥 魏敏 江森 王欢[1] 郭学武[1,2] 肖冬光[1,2] 武晓乐 陈叶福[1,2] KANG Xinyue;WEI Min;JIANG Sen;WANG Huan;GUO Xuewu;XIAO Dongguang;WU Xiaole;CHEN Yefu(College of Biotechnology,Tianjin University of Science and Technology,Tianjin 300457,China;Key Laboratory of Fermentation Microbiology of Ministry of Education,Tianjin University of Science and Technology,Tianjin 300457,China)

机构地区：[1]天津科技大学生物工程学院,天津300457 [2]工业发酵微生物教育部重点实验室(天津科技大学),天津300457

出　　处：《食品与发酵工业》2022年第23期17-24,共8页Food and Fermentation Industries

基　　金：国家重点研发计划项目(2018YFC1604103)。

摘　　要：高级醇是影响中国黄酒风味和饮用品质的重要因素之一,适量高级醇可赋予黄酒醇柔、协调的口感,但高级醇过高会导致酒体产生杂醇味,且有强烈的致醉性。在酿酒酵母中,过表达ALD6基因可以显著降低高级醇的生成量,但是过多乙酸的生成会抑制细胞的生长和代谢。由于黄酒发酵是双边发酵,可以通过筛选合适的糖诱导型启动子调控ALD6的表达,在降低高级醇生成量的同时减弱其对细胞生长的抑制作用。该研究选取了6个HXT系列的糖诱导型启动子P_(hxt1)、P_(hxt2)、P_(hxt3)、P_(hxt4)、P_(hxt5)和P_(hxt7)调控乙醛脱氢酶基因ALD6的表达,黄酒发酵结果显示,相较于出发菌株a17,各诱导型重组菌株总高级醇生成量分别下降22.29%、19.26%、42.56%、37.84%、16.72%和30.74%。对比组成型重组菌株a-P_(pgk1)-A和诱导型重组菌株a-P_(hxt3)-A发现,二者相较于出发菌株a17均可显著降低总高级醇的生成,但与a-P_(pgk1)-A相比,a-P_(hxt3)-A的生长及发酵性能与a17基本一致,在降低高级醇生成量的同时减弱了过表达ALD6产生乙酸对发酵的不利影响。Higher alcohols are one of the important factors affecting the flavor and drinking quality of Chinese rice wine.A moderate amount of higher alcohols make the rice wine taste full,soft,mellow and harmonious,but high concentration of higher alcohols will lead to fusel flavor and strong intoxication.Overexpression of ALD6 can significantly reduce the production of higher alcohols,but the production of excessive acetic acid inhibits cell growth and metabolism in the Saccharomyces cerevisiae.Since rice wine fermentation is bilateral fermentation,the expression of ALD6 can be regulated by screening suitable sugar-inducible promoters,which can reduce the production of higher alcohols and at the same time weaken its inhibitory effect on cell growth.In this study,six HXT series sugar-inducible promoters P_(hxt1),P_(hxt2),P_(hxt3),P_(hxt4),P_(hxt5) and P_(hxt7) were selected to regulate the expression of acetaldehyde dehydrogenase gene ALD6.The fermentation results of rice wine showed that compared with the control strain a17,the total production of higher alcohols of the inducible recombine strains decreased by 22.29%,19.26%,42.56%,37.84%,16.72%and 30.74%respectively.In addition,the fermentation results showed that compared with the a17,the constitutive recombine strain a-P_(pgk1)-A and the inducible recombine strain a-P_(hxt3)-A can significantly reduce the production of total higher alcohols,but the growth of a-P_(hxt3)-A was basically the same as a17.

关 键 词：高级醇 糖诱导型启动子(P hxts) 乙醛脱氢酶 黄酒 酿酒酵母 

分 类 号：TS262.4[轻工技术与工程—发酵工程]