产CCDs酿酒酵母菌株的构建及应用研究

Construction and Application of CCDs Enzyme-producing Saccharomyces Cerevisiae Strains

类胡萝卜素双加氧裂解酶(Carotenoid cleavage dioxygenases,CCDs)可催化类胡萝卜素氧化裂解产生降异戊二烯类香气化合物。本研究利用同源重组技术在酿酒酵母BY4741基因组LPP1位点整合了葡萄VvCCD1基因得到重组菌株QGXH1,并探明了VvCCD1酶催化裂解β-胡萝卜素的最适条件(pH7、温度40℃)及香气化合物产物(β-紫罗兰酮、β-环柠檬醛、二氢猕猴桃内酯等)。以‘霞多丽’葡萄为原料,将菌株QGXH1与酿酒酵母EC1118顺序接种发酵,相比于只接种EC1118,β-紫罗兰酮和β-大马士酮的含量分别提高了125%、60%。本研究为VvCCD 1基因克隆表达提供了参考,为优化葡萄酒品种香气及富含类胡萝卜素的植物资源高值化加工创造了条件。

Carotenoid cleavage dioxygenases(CCDs)catalyze the oxidative cleavage of carotenoids to produce descending isoprenoid aroma compounds.In this study,homologous recombination technology was used to integrate grape VvCCD1 at LPP1 site of Saccharomyces cerevisiae BY4741 genome to obtain recombinant strain QGXH1,and explored the optimal conditions for the catalytic cleavage ofβ-carotene by VvCCD1(pH7 and temperature 40℃)and the products of the aroma compounds(β-ionone,β-cyclic citrulline,and dihydronic kiwifoliolactone,etc.).Using'Chardonnay'grapes as the raw material,strain QGXH1 was sequentially inoculated and fermented with Saccharomyces cerevisiae EC1118,and the contents ofβ-ionone andβ-damascenone were increased by 125%and 60%,respectively,compared to inoculation with EC1118 only.This study provides a reference for the clonal expression of VvCCD1 and creates conditions for optimizing the variety aroma of wine and the high-value processing of carotenoid-rich plant resources.