Sun Jinfeng, Wang Jie, Tian Kangming, Dong Zixing, Liu Xiaoguang, Permaul Kugenthiren, Singh Suren, Prior Bernard A, Wang Zhengxiang
School of Biotechnology, Center for Bioresource and Bioenergy, Jiangnan University, 1800 Lihu Avenue, Wuxi, 214122, China.
School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1st East Meicheng Road, Huaian, 223003, China.
Biotechnol Lett. 2018 May;40(5):781-788. doi: 10.1007/s10529-018-2537-0. Epub 2018 Mar 21.
To develop a xylose-nonutilizing Escherichia coli strain for ethanol production and xylose recovery.
Xylose-nonutilizing E. coli CICIM B0013-2012 was successfully constructed from E. coli B0013-1030 (pta-ack, ldhA, pflB, xylH) by deletion of frdA, xylA and xylE. It exhibited robust growth on plates containing glucose, arabinose or galactose, but failed to grow on xylose. The ethanol synthesis pathway was then introduced into B0013-2012 to create an ethanologenic strain B0013-2012PA. In shaking flask fermentation, B0013-2012PA fermented glucose to ethanol with the yield of 48.4 g/100 g sugar while xylose remained in the broth. In a 7-l bioreactor, B0013-2012PA fermented glucose, galactose and arabinose in the simulated corncob hydrolysate to 53.4 g/l ethanol with the yield of 48.9 g/100 g sugars and left 69.6 g/l xylose in the broth, representing 98.6% of the total xylose in the simulated corncob hydrolysate.
By using newly constructed strain B0013-2012PA, we successfully developed an efficient bioprocess for ethanol production and xylose recovery from the simulated corncob hydrolysate.
构建一株不利用木糖的大肠杆菌菌株用于乙醇生产和木糖回收。
通过缺失frdA、xylA和xylE基因，从大肠杆菌B0013 - 1030（pta - ack、ldhA、pflB、xylH）成功构建出不利用木糖的大肠杆菌CICIM B0013 - 2012。它在含有葡萄糖、阿拉伯糖或半乳糖的平板上生长旺盛，但在木糖上不能生长。然后将乙醇合成途径导入B0013 - 2012中，构建出乙醇生产菌株B0013 - 2012PA。在摇瓶发酵中，B0013 - 2012PA将葡萄糖发酵为乙醇，产率为48.4 g/100 g糖，而木糖则保留在发酵液中。在7 L生物反应器中，B0013 - 2012PA将模拟玉米芯水解液中的葡萄糖、半乳糖和阿拉伯糖发酵为53.4 g/L乙醇，产率为48.9 g/100 g糖，并在发酵液中留下69.6 g/L木糖，占模拟玉米芯水解液中总木糖的98.6%。
利用新构建的菌株B0013 - 2012PA，我们成功开发了一种从模拟玉米芯水解液中高效生产乙醇和回收木糖的生物工艺。
