State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China.
School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China.
Bioresour Technol. 2019 Jan;271:266-273. doi: 10.1016/j.biortech.2018.09.095. Epub 2018 Sep 19.
Resistance to furan derivatives and phenolic compounds plays an important role in the use of lignocellulosic biomass for biological production of chemicals and fuels. This study confirmed that expression of short-chain dehydrogenase/reductase (SDR) from Clostridium beijerinckii NCIMB 8052 significantly improved the tolerance of C. tyrobutyricum to furfural due to the enhanced activity for furfural reduction. And on this basis, co-expression of SDR and heat shock chaperones GroESL could simultaneously enhance the tolerance of C. tyrobutyricum to furan derivatives and phenolic compounds, which were the main inhibitors presented in dilute-acid lignocellulosic hydrolysates. Consequently, the recombinant strain ATCC 25755/sdr+groESL exhibited good performance in butyric acid production with corncob acid hydrolysate as the substrate. Batch fermentation in bioreactor showed that the butyrate produced by ATCC 25755/sdr+groESL was 32.8 g/L, increased by 28.1% as compared with the wild-type strain. Meanwhile, the butyrate productivity increased from 0.19 g/L·h to 0.29 g/L·h.
对糠醛衍生物和酚类化合物的抗性在利用木质纤维素生物质进行化学品和燃料的生物生产中起着重要作用。本研究证实，来自拜氏梭菌 NCIMB 8052 的短链脱氢酶/还原酶 (SDR) 的表达显著提高了 C. tyrobutyricum 对糠醛的耐受性，因为糠醛还原的活性增强。在此基础上，SDR 和热休克伴侣 GroESL 的共表达可以同时提高 C. tyrobutyricum 对呋喃衍生物和酚类化合物的耐受性，这些是稀酸木质纤维素水解物中主要的抑制剂。因此，重组菌株 ATCC 25755/sdr+groESL 在以玉米芯酸水解物为底物进行丁酸生产时表现出良好的性能。生物反应器中的分批发酵表明，与野生型菌株相比，ATCC 25755/sdr+groESL 产生的丁酸增加了 28.1%，达到 32.8 g/L。同时，丁酸的生产能力从 0.19 g/L·h 提高到 0.29 g/L·h。
