Department of Bioengineering, Rice University, 6500 Main Street, Houston, TX, 77030, USA.
Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Valparaiso, Chile.
J Ind Microbiol Biotechnol. 2018 Jan;45(1):53-60. doi: 10.1007/s10295-017-1991-3. Epub 2017 Dec 1.
Several metabolic engineered Escherichia coli strains were constructed and evaluated for four-carbon dicarboxylic acid production. Fumarase A, fumarase B and fumarase C single, double and triple mutants were constructed in a ldhA adhE mutant background overexpressing the pyruvate carboxylase from Lactococcus lactis. All the mutants produced succinate as the main four-carbon (C4) dicarboxylic acid product when glucose was used as carbon source with the exception of the fumAC and the triple fumB fumAC deletion strains, where malate was the main C4-product with a yield of 0.61-0.67 mol (mole glucose). Additionally, a mdh mutant strain and a previously engineered high-succinate-producing strain (SBS550MG-Cms pHL413-Km) were investigated for aerobic malate production from succinate. These strains produced 40.38 mM (5.41 g/L) and 50.34 mM (6.75 g/L) malate with a molar yield of 0.53 and 0.55 mol (mole succinate), respectively. Finally, by exploiting the high-succinate production capability, the strain SBS550MG-Cms243 pHL413-Km showed significant malate production in a two-stage process from glucose. This strain produced 133 mM (17.83 g/L) malate in 47 h, with a high yield of 1.3 mol (mole glucose) and productivity of 0.38 g L h.
构建了几种代谢工程大肠杆菌菌株，并对其进行了评估，以生产四碳二羧酸。在过表达来自乳球菌的丙酮酸羧化酶的 ldhA adhE 突变体背景下，构建了延胡索酸酶 A、B 和 C 的单、双和三重突变体。当以葡萄糖为碳源时，除了 fumAC 和 triple fumB fumAC 缺失菌株外，所有突变株都以琥珀酸为主要四碳 (C4) 二羧酸产物，其中苹果酸是主要的 C4 产物，产量为 0.61-0.67 mol（摩尔葡萄糖）。此外，还研究了一个 mdh 突变株和一个先前构建的高产琥珀酸菌株 (SBS550MG-Cms pHL413-Km) 用于从琥珀酸有氧生产苹果酸。这些菌株分别产生了 40.38 mM（5.41 g/L）和 50.34 mM（6.75 g/L）的苹果酸，摩尔收率分别为 0.53 和 0.55 mol（摩尔琥珀酸）。最后，通过利用高琥珀酸生产能力，菌株 SBS550MG-Cms243 pHL413-Km 在从葡萄糖的两阶段过程中表现出显著的苹果酸生产能力。该菌株在 47 h 内生产了 133 mM（17.83 g/L）的苹果酸，摩尔收率为 1.3 mol（摩尔葡萄糖），产率为 0.38 g L h。
