Enhanced solvent production by metabolic engineering of a twin-clostridial consortium.
Enhanced solvent production by metabolic engineering of a twin-clostridial consortium.
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DOI：
10.1016/j.ymben.2016.10.013
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发表时间：
2017
影响因子：
8.4
通讯作者：
Zhiqiang Wen;N. Minton;Ying Zhang;Qi Li;Jinle Liu;Yu Jiang;Sheng Yang
中科院分区：
文献类型：
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作者：
Zhiqiang Wen;N. Minton;Ying Zhang;Qi Li;Jinle Liu;Yu Jiang;Sheng Yang
使用单一工艺微生物从木质纤维素原料有效发酵生产溶剂（丙酮、正丁醇和乙醇）尚未得到证实。在此，我们开发了一种基于双梭菌财团的联合生物处理（CBP），该双梭菌财团由梭菌cellulovorans和拜氏梭菌组成，能够从碱提取的脱壳玉米棒（AECC）中生产纤维素丁醇。为了实现这一点，一个遗传系统被开发为C。在本发明的方法中，使用噬纤维素酶，并用于敲除编码乙酸激酶（Clocel_1892）和乳酸脱氢酶（Clocel_1533）的基因，并过表达编码丁酸激酶（Clocel_3674）的基因，从而将碳通量拉向丁酸生产。平行地，为了增强乙醇生产，使用CRISPR干扰（CRISPRi）下调推定的氢化酶基因（Clocel_2243）的表达。同时，在C. L.中构建了有机酸再同化相关基因ctfAB（cbei_3833/3834）和戊糖利用相关基因xylR（cbei_2385）和xylT（cbei_0109）。beijerinckiito提高溶剂生产。工程化的双梭菌聚生体显示分解83.2g/L的AECC并产生22.1g/L的溶剂（4.25g/L丙酮、11.5g/L丁醇和6.37g/L乙醇）。丙酮-丁醇-乙醇（ABE）的这种滴度接近于从淀粉原料获得的滴度。所开发的双梭菌财团作为一个有前途的平台，ABE发酵从木质纤维素CBP。
The efficient fermentative production of solvents (acetone,n-butanol, and ethanol) from a lignocellulosic feedstock using a single process microorganism has yet to be demonstrated. Herein, we developed a consolidated bioprocessing (CBP) based on a twin-clostridial consortium composed of Clostridium cellulovorans and Clostridium beijerinckii capable of producing cellulosic butanol from alkali-extracted, deshelled corn cobs (AECC). To accomplish this a genetic system was developed forC. cellulovoransand used to knock out the genes encoding acetate kinase (Clocel_1892) and lactate dehydrogenase (Clocel_1533), and to overexpress the gene encoding butyrate kinase (Clocel_3674), thereby pulling carbon flux towards butyrate production. In parallel, to enhance ethanol production, the expression of a putative hydrogenase gene (Clocel_2243) was down-regulated using CRISPR interference (CRISPRi). Simultaneously, genes involved in organic acids reassimilation (ctfAB, cbei_3833/3834) and pentose utilization (xylR, cbei_2385andxylT, cbei_0109) were engineered inC. beijerinckiito enhance solvent production. The engineered twin-clostridia consortium was shown to decompose 83.2 g/L of AECC and produce 22.1 g/L of solvents (4.25 g/L acetone, 11.5 g/L butanol and 6.37 g/L ethanol). This titer of acetone-butanol-ethanol (ABE) approximates to that achieved from a starchy feedstock. The developed twin-clostridial consortium serves as a promising platform for ABE fermentation from lignocellulose by CBP.