Engineering of Corynebacterium glutamicum as a prototrophic pyruvate-producing strain: Characterization of a ramA-deficient mutant and its application for metabolic engineering
Engineering of Corynebacterium glutamicum as a prototrophic pyruvate-producing strain: Characterization of a ramA-deficient mutant and its application for metabolic engineering
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将谷氨酸棒杆菌改造为原养型丙酮酸生产菌株：ramA 缺陷突变体的表征及其在代谢工程中的应用
DOI：
10.1080/09168451.2018.1527211
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Matsushita Kazunobu
中科院分区：
文献类型：
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作者：
Kataoka Naoya;Vangnai Alisa S.;Pongtharangkul Thunyarat;Yakushi Toshiharu;Wada Masaru;Yokota Atsushi;Matsushita Kazunobu
为了构建一株高效利用葡萄糖生产丙酮酸的原养型谷氨酸棒杆菌，研究了拉马（一种负责激活氧化三羧酸循环的全局调节因子）失活对葡萄糖代谢的影响。与野生型相比，Δ ramA显示出比葡萄糖消耗速率增加，生长降低，丙酮酸产量相当，乳酸和乙酸的形成更高，琥珀酸和2-酮戊二酸的积累更低。观察到Δ拉马的丙酮酸脱氢酶复合物活性显著降低，表明Δ拉马中TCA循环的碳流减少。为了产生有效的丙酮酸生产者，在缺乏所有已知的乳酸和乙酸产生途径中涉及的基因的菌株中删除theramA基因。所得突变体从222 mM葡萄糖产生161 mM丙酮酸，这显著高于亲本（89.3 mM; 1.80倍）。
To construct a prototrophicCorynebacterium glutamicumstrain that efficiently produces pyruvate from glucose, the effects of inactivating RamA, a global regulator responsible for activating the oxidative tricarboxylic acid (TCA) cycle, on glucose metabolism were investigated. ΔramAshowed an increased specific glucose consumption rate, decreased growth, comparable pyruvate production, higher formation of lactate and acetate, and lower accumulation of succinate and 2-oxoglutarate compared to the wild type. A significant decrease in pyruvate dehydrogenase complex activity was observed for ΔramA, indicating reduced carbon flow to the TCA cycle in ΔramA. To create an efficient pyruvate producer, theramAgene was deleted in a strain lacking the genes involved in all known lactate- and acetate-producing pathways. The resulting mutant produced 161 mM pyruvate from 222 mM glucose, which was significantly higher than that of the parent (89.3 mM; 1.80-fold).