Zhao Shuai, Mai Rong-Ming, Zhang Ting, Feng Xiang-Zhao, Li Wen-Tong, Wang Wen-Xuan, Luo Xue-Mei, Feng Jia-Xun
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning, China.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning, China.
Bioresour Technol. 2022 May;351:127058. doi: 10.1016/j.biortech.2022.127058. Epub 2022 Mar 23.
Genetic engineering is an efficient approach to improve fungal bioproducts, but the specific targets are limited. In this study, it was found that the key transcription repressor CxrC of Penicillium oxalicum could physically interact with the translational elongation factor eEF1A that positively regulated the production of plant-biomass-degrading enzymes by the fungus under Avicel induction. Simultaneously deletion of the cxrC and overexpression of the eEF1A in the strain Δku70 resulted in 55.4%-314.6% higher production of cellulase, xylanase and raw-starch-degrading enzymes than that of the start strain Δku70. Transcript abundance of the genes encoding predominant cellulases, xylanases and raw-starch-degrading enzymes were significantly upregulated in the mutant ΔcxrC::eEF1A. The ΔcxrC::eEF1A enhanced saccharification efficiency of raw cassava flour by 9.3%-15.5% at early-middle stage of hydrolysis in comparison with Δku70. The obtained knowledges expanded the sources used as effective targets for increased production of plant-biomass-degrading enzymes by fungi.
基因工程是提高真菌生物产品的一种有效方法，但具体的靶点有限。在本研究中，发现草酸青霉的关键转录抑制因子CxrC可与翻译延伸因子eEF1A发生物理相互作用，在微晶纤维素诱导下，eEF1A对该真菌植物生物质降解酶的产生具有正向调控作用。在Δku70菌株中同时缺失cxrC并过表达eEF1A，与起始菌株Δku70相比，纤维素酶、木聚糖酶和生淀粉降解酶的产量提高了55.4%-314.6%。在突变体ΔcxrC::eEF1A中，编码主要纤维素酶、木聚糖酶和生淀粉降解酶的基因转录丰度显著上调。与Δku70相比，ΔcxrC::eEF1A在水解的中前期将木薯生粉的糖化效率提高了9.3%-15.5%。所获得的知识拓展了可作为提高真菌植物生物质降解酶产量有效靶点的来源。
