Corynebacterium glutamicum, an established microbial cell factory for the biotechnological production of amino acids, was recently genetically engineered for aerobic succinate production from glucose in minimal medium. In this work, the corresponding strains were transformed with plasmid pVWEx1-glpFKD coding for glycerol utilization genes from Escherichia coli. This plasmid had previously been shown to allow growth of C. glutamicum with glycerol as sole carbon source. The resulting strains were tested in minimal medium for aerobic succinate production from glycerol, which is a by-product in biodiesel synthesis. The best strain BL-1/pVWEx1-glpFKD formed 79 mM (9.3 g l−1) succinate from 375 mM glycerol, representing 42% of the maximal theoretical yield under aerobic conditions. A specific succinate production rate of 1.55 mmol g−1 (cdw) h−1 and a volumetric productivity of 3.59 mM h−1 were obtained, the latter value representing the highest one currently described in literature. The results demonstrate that metabolically engineered strains of C. glutamicum are well suited for aerobic succinate production from glycerol.
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机译：谷氨酸棒杆菌是一家成熟的微生物细胞工厂，用于氨基酸的生物技术生产，最近经过基因工程改造，可在极少的培养基中从葡萄糖中产生有氧琥珀酸。在这项工作中，用编码来自大肠杆菌的甘油利用基因的质粒pVWEx1-glpFKD转化了相应的菌株。先前已证明该质粒可以用甘油作为唯一碳源来生长谷氨酸棒杆菌。在基本培养基中测试了所得菌株从甘油产生好氧琥珀酸酯的能力，而甘油是生物柴油合成中的副产物。最佳菌株BL-1 / pVWEx1-glpFKD由375 mM甘油形成79 mM（9.3 g l -1 ）琥珀酸盐，占有氧条件下最大理论收率的42％。琥珀酸的单位生产率为1.55 mmol g -1 （cdw）h -1 ，体积生产率为3.59 mM h -1 ，后者代表目前文献中描述的最高值。结果表明，经代谢工程改造的谷氨酸棒杆菌菌株非常适合于由甘油生产好氧琥珀酸酯。
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