麦芽糖酶基因MAL62的不同截断变体对面包酵母发酵性能的影响

Effects of Different Truncated Variants of Maltase Gene MAL62 on Fermentation of Yeast

为了探究麦芽糖酶基因MAL62的不同截断变体对面包酵母发酵性能的影响,以面包酵母工业菌株BY-14基因组为模板,通过PCR获得编码麦芽糖酶的3种不同长度氨基酸的DNA序列,研究改造后菌株的发酵力、麦芽糖消耗速率及麦芽糖酶活力的变化,从而揭示编码麦芽糖酶的氨基酸与其功能之间的关系。结果表明:含有编码麦芽糖酶不同长度基因的面包酵母菌株的发酵力、麦芽糖消耗速率及麦芽糖酶活力均优于含有未改造的麦芽糖酶的重组菌株,说明敲除催化区域外的氨基酸不会影响面包酵母中麦芽糖酶的主要性能和面包酵母菌株的无糖面团发酵能力。

To investigate the effect of different truncated variants of maltase gene MAL62 on the fermentation of baker’s yeast,DNA sequences of three different length of amino acid encoded maltase from baker’s yeast BY-14 was amplified via PCR.The fermenting abilities,maltose utilization and maltase activity of all the recombinant strains were investigated to reveal the relationship between the amino acid encoded maltase and its function.The result showed that the fermenting abilities,maltose utilization and maltase activity of the baker’s yeast strain containing molecularly modified maltase were slightly better than the recombinant strain containing unmodified maltase.It is indicated that knocking out amino acid outside the catalytic region can affect neither the main properties of maltase in baker’s yeast,nor the ability of baker’s yeast to ferment sugar-free dough.