Department of Molecular Science and Technology, Ajou University, Woncheon-dong, Yeongtong-gu, Suwon 443-749, Republic of Korea.
Bioresour Technol. 2013 Feb;130:288-95. doi: 10.1016/j.biortech.2012.11.148. Epub 2012 Dec 13.
Sucrose is one of the most promising carbon sources for industrial fermentation. We expressed synthetic modules expressing genes of the PEP-PTS and non-PTS pathways in Escherichia coli K12 for comparison. We selected PEP-PTS pathway genes of Lactobacillus plantarum and Staphylococcus xylosus and non-PTS pathway genes of sucrose-utilizing (Scr(+)) E. coli EC3132. Switchable Scr(+) modules expressing E. coli EC3132 non-PTS genes conferred better sucrose-utilizing ability on Scr(-)E. coli K12 than E. coli EC3132. Scr(+) modules expressing S. xylosus PEP-PTS genes conferred a sucrose-utilizing ability on E. coli K12. Among L. plantarum PEP-PTS genes, SacA(LP) and SacK(LP) were functional in E. coli K12. CscA(EC)-CscB(EC)-CscK(EC) (non-PEP-PTS module) or ScrA(SX)-SacA(LP)-SacK(LP) (PEP-PTS module) was introduced to a diapolycopene-producing E. coli strain. In both Scr(+)E. coli K12, the sucrose-utilizing ability of the modules was not affected by diapolycopene formation, indicating that the modular Scr(+) systems could be employed for developing sustainable bioprocesses using sucrose.
蔗糖是工业发酵最有前途的碳源之一。我们在大肠杆菌 K12 中表达了表达 PEP-PTS 和非 PTS 途径基因的合成模块进行比较。我们选择了植物乳杆菌和葡萄球菌木糖亚种的 PEP-PTS 途径基因和利用蔗糖（Scr(+)）的大肠杆菌 EC3132 的非 PTS 途径基因。表达大肠杆菌 EC3132 非 PTS 基因的可切换 Scr(+)模块赋予 Scr(-)大肠杆菌 K12 比大肠杆菌 EC3132 更好的蔗糖利用能力。表达葡萄球菌木糖亚种 PEP-PTS 基因的 Scr(+)模块赋予了大肠杆菌 K12 蔗糖利用能力。在植物乳杆菌的 PEP-PTS 基因中，SacA(LP)和 SacK(LP)在大肠杆菌 K12 中具有功能。CscA(EC)-CscB(EC)-CscK(EC)（非 PEP-PTS 模块）或 ScrA(SX)-SacA(LP)-SacK(LP)（PEP-PTS 模块）被引入二氢番茄红素生产大肠杆菌菌株。在两种 Scr(+)大肠杆菌 K12 中，模块的蔗糖利用能力不受二氢番茄红素形成的影响，表明模块化 Scr(+)系统可用于开发利用蔗糖的可持续生物工艺。
