Laboratory of Agricultural and Molecular Microbiology, Dept Tecnologia Agroindustrial e Socioeconomia Rural, Centro de Ciências Agrárias, Universidade Federal de São Carlos, Via Anhanguera, km 174, 13600-970 Araras, São Paulo State, Brazil.
FEMS Yeast Res. 2021 Jan 6;20(8). doi: 10.1093/femsyr/foaa065.
The peculiarities of Brazilian fuel ethanol fermentation allow the entry of native yeasts that may dominate over the starter strains of Saccharomyces cerevisiae and persist throughout the sugarcane harvest. The switch from the use of baker's yeast as starter to selected budding yeasts obtained by a selective pressure strategy was followed by a wealth of genomic information that enabled the understanding of the superiority of selected yeast strains. This review describes how the process of yeast selection evolved in the sugarcane-based bioethanol industry, the selection criteria and recent advances in genomics that could advance the fermentation process. The prospective use of genetically modified yeast strains, specially designed for increased robustness and product yield, with special emphasis on those obtained by the CRISPR (clustered regularly interspaced palindromic repeats)-Cas9 (CRISPR-associated protein 9) genome-editing approach, is discussed as a possible solution to confer higher performance and stability to the fermentation process for fuel ethanol production.
巴西燃料乙醇发酵的特点允许本土酵母进入，这些酵母可能会超过酿酒酵母的起始菌株，并在整个甘蔗收获期持续存在。从使用面包酵母作为起始菌株转变为使用选择性压力策略获得的选定出芽酵母，随后获得了大量基因组信息，使人们能够了解选定酵母菌株的优越性。本文综述了酵母选择过程如何在基于甘蔗的生物乙醇工业中发展，选择标准以及基因组学的最新进展如何推动发酵过程。还讨论了专门设计用于提高鲁棒性和产物产量的遗传修饰酵母菌株的预期用途，特别强调了通过 CRISPR（成簇规律间隔短回文重复）-Cas9（CRISPR 相关蛋白 9）基因组编辑方法获得的酵母菌株，作为为燃料乙醇生产赋予发酵过程更高性能和稳定性的一种可能解决方案。
