Ma Cui, Zhao Xinqing, Li Qian, Zhang Mingming, Kim Jin Soo, Bai Fengwu
School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, Liaoning, China.
Sheng Wu Gong Cheng Xue Bao. 2013 May;29(5):612-9.
Breeding of robust industrial Saccharomyces cerevisiae strains with high ethanol tolerance is of great significance for efficient fuel ethanol production. Zinc finger proteins play important roles in gene transcription and translation, and exerting control on the regulation of multiple genes. The sequence and localization of the zinc finger motif can be designed and engineered, and the artificial zinc finger protein can be used to regulate celluar metabolism. Stress tolerance of microbial strains is related to multiple genes. Therefore, it is possible to use artificially-designed zinc finger proteins to breed stress tolerant strains. In this study, a library containing artificial zinc finger protein encoding genes was transformed into the model yeast strain S288c. A recombinant strain named M01 with improved ethanol tolerance was obtained. The plasmid in M01 was isolated, and then transformed into the industrial yeast strain Sc4126. Ethanol tolerance of the recombinant strain of Sc4126 were significantly improved. When high gravity ethanol fermentation using 250 g/L glucose was performed, comparing with the wild-type strain, fermentation time of the recombinant strain was decreased by 24 h and the final ethanol concentration was enhanced by 6.3%. The results of this study demonstrate that artificial zinc finger proteins are able to exert control on stress tolerance of yeast strains, and these results provide basis to construct robust industrial yeast strains for efficient ethanol fermentation.
培育具有高乙醇耐受性的健壮工业酿酒酵母菌株对于高效生产燃料乙醇具有重要意义。锌指蛋白在基因转录和翻译中发挥重要作用，并对多个基因的调控施加控制。锌指基序的序列和定位可以进行设计和改造，人工锌指蛋白可用于调节细胞代谢。微生物菌株的胁迫耐受性与多个基因相关。因此，有可能利用人工设计的锌指蛋白培育耐胁迫菌株。在本研究中，将一个包含人工锌指蛋白编码基因的文库转化到模式酵母菌株S288c中。获得了一株乙醇耐受性提高的重组菌株M01。分离出M01中的质粒，然后将其转化到工业酵母菌株Sc4126中。Sc4126重组菌株的乙醇耐受性显著提高。当使用250 g/L葡萄糖进行高浓度乙醇发酵时，与野生型菌株相比，重组菌株的发酵时间缩短了24 h，最终乙醇浓度提高了6.3%。本研究结果表明，人工锌指蛋白能够对酵母菌株的胁迫耐受性施加控制，这些结果为构建用于高效乙醇发酵的健壮工业酵母菌株提供了依据。
