摘要
[目的]增强工业用酿酒酵母菌株对甘蔗糖蜜中非还原糖的利用,提高糖蜜发酵乙醇产率。[方法]构建载体p YX212-agl3,分别在载体的TPI启动子和终止子5’端加上10 bp的酵母转座子重复序列,PCR扩增获得TPIP-agl3-TPIT片段,将该片段电转化至工业用野生型酿酒酵母MF1001的单倍体细胞中,复倍后经过YPR培养基初筛和YPSR培养基复筛。[结果]获得的MFA1001-3菌株分别在10锤、20锤、30锤和40锤的甘蔗糖蜜培养基中细胞的生长速率、酒精发酵浓度、对糖分的利用能力均有所增强,在40锤糖蜜中的差异最为明显,最大细胞数增加了58.7%,最大产酒率提高了4.5%,发酵结束后醪液中的总糖浓度减少了23.6%,还原糖浓度增加了15.05%。[结论]与出发菌株相比重组菌株发酵醪液中最终还原糖浓度增加而总糖浓度却减少,说明用该方法整合表达α-半乳糖苷酶的重组菌株确实有效地水解了糖蜜中的部分非还原糖同时提高了对总糖的利用率。
[ Objective] Enhanced the ability of industrial Saccharomyces cerevisiae for using reducing sugar in sugarcane mo- lasses, and improved the fermentation product of ethanol. [ Methods] Firstly constructed the vector of pYX212 -ag13, then got the segment of TPIP - agl3 - TPIT by PCR with 10 bp repetitive sequence of Saccharomyces cerevisiae transposon respectively on 5＇ terminal of TPI promoter and terminator. TPIP - agl3 - TPIT segment was transformed into the haploid cell of wild type Saccharomyces cerevisiae MF1001 strain,mated to diploid cells and screened with YPR medium and YPSR medium. [ Results] Finally got a recombination strain MFAIO01 -3 ,whose growth rate, ethanol production, ability of sugar utilization were all en- hanced in 10,20,30,40 Brix sugar - cane molasses. Obvious differences appeared in 40 Brix broth,the biggest number of cell increased 58.7%, the highest ethanol production increased 4.5 %, at the end of fermentation, the concentration of total sugar decreased 23.6% and the concentration of reducing sugar increased 15.05 %. [ Conclusion ] Compared with original strain, the final concentrations of reducing sugar were increased while the concentrations of total sugar were decreased, these results dem-onstrated that the strain recombined using the method of this study indeed hydrolyze non reducing sugar of molasses effectively and enhance the ability of using the sugar.
出处
《生物技术》
北大核心
2017年第2期117-122,共6页
Biotechnology
基金
广西科学研究与技术开发计划项目(“木质纤维素水解技术的引进与合作研究”,No.桂科合15104001-8
“蔗渣清洁、高效转化乙醇关键技术引进与合作研究”,No.桂科合14123001-6
“蔗渣乙醇高效低成本清洁生产关键技术开发及示范”,No.桂科重14122004-3
“糖蜜乙醇高效清洁生产关键技术及示范”,No.桂科重14122004-1
“甘蔗渣产酒精新型酵母基因组研究”,No.桂科攻1517-07)
广西自然科学基金项目(“酿酒酵母工业菌株呼吸突变体生理特性及其基因变异的研究”,No.2014GXNSFAA118103)
广西科学院基本科研业务费资助项目(“基金重组构建甘蔗糖蜜酒精高效发酵菌株研究”,No.11YJ24SW10)
关键词
Α-半乳糖苷酶
酿酒酵母
转座子重复序列
基因重组
糖蜜发酵
非还原糖利用
α - galactosidase gene, Saccharomyces cerevisiae, repetitive sequence of transposon, gene recombination, molasses fermentation, using non reducing sugar
