在明串珠菌中构建葡萄糖到甘露醇的转化体系

Enhanced biosynthesis of mannitol in Leuconostoc sp. expressed mt1d-m1p

为了进一步提高甘露醇产量,在明串珠菌构建了葡萄糖到甘露醇的转化体系。通过2次同源重组,将mt1d-m1p表达盒串联体定点插入到染色体上。以90g/L蔗糖为底物时,野生型菌株的甘露醇产量为31.48g/L,Δaldh::(mt1d-m1p)为42.63g/L,Δaldh::(mt1d-m1p)Δdts::amy为43.47g/L,Δaldh::(mt1d-m1p)Δdts::(mt1d-m1p)为45.74g/L,Δdts1ΔD-ldhΔpat::mdhΔstpk::mdhΔfk::mdhΔaldh::(mt1d-m1p)为47.26g/L。增加甘露醇的合成途径是增产的手段之一。

In order to further increase mannitol production from sucrose in Leuconostoc sp.,a mt1d-m1p expression cassette was site-directly integrated onto its chromosome.The resulting strains,Δaldh::(mt1d-m1p),Δaldh::(mt1d-m1p)Δdts::amy,Δaldh::(mt1d-m1p)Δdts::(mt1d-m1p),andΔdts1ΔD-ldhΔpat::mdhΔstpk::mdhΔfk::mdhΔaldh::(mt1d-m1p)produced 42.63,43.47,45.74 and 47.26 g/L mannitol from 90 g/L sucrose.In comparison,wild type only produced 31.48 g/L mannitol.In conclusion,increasing the synthetic route of mannitol from glucose is one of the means to increase its production.