Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India.
Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India.
Adv Appl Microbiol. 2021;116:1-98. doi: 10.1016/bs.aambs.2021.03.003. Epub 2021 May 7.
Microbial lipid production has been studied extensively for years; however, lipid metabolic engineering in many of the extraordinarily high lipid-accumulating yeasts was impeded by inadequate understanding of the metabolic pathways including regulatory mechanisms defining their oleaginicity and the limited genetic tools available. The aim of this review is to highlight the prominent oleaginous yeast genera, emphasizing their oleaginous characteristics, in conjunction with diverse other features such as cheap carbon source utilization, withstanding the effect of inhibitory compounds, commercially favorable fatty acid composition-all supporting their future development as economically viable lipid feedstock. The unique aspects of metabolism attributing to their oleaginicity are accentuated in the pretext of outlining the various strategies successfully implemented to improve the production of lipid and lipid-derived metabolites. A large number of in silico data generated on the lipid accumulation in certain oleaginous yeasts have been carefully curated, as suggestive evidences in line with the exceptional oleaginicity of these organisms. The different genetic elements developed in these yeasts to execute such strategies have been scrupulously inspected, underlining the major types of newly-found and synthetically constructed promoters, transcription terminators, and selection markers. Additionally, there is a plethora of advanced genetic toolboxes and techniques described, which have been successfully used in oleaginous yeasts in the recent years, promoting homologous recombination, genome editing, DNA assembly, and transformation at remarkable efficiencies. They can accelerate and effectively guide the rational designing of system-wide metabolic engineering approaches pinpointing the key targets for developing industrially suitable yeast strains.
多年来，人们对微生物脂质生产进行了广泛的研究；然而，在许多具有极高脂质积累能力的酵母中，脂质代谢工程受到对代谢途径的理解不足的阻碍，包括定义其油脂特性的调控机制以及可用的有限遗传工具。本综述的目的是强调突出的产油酵母属，强调它们的产油特性，以及其他各种特征，如廉价碳源的利用、耐受抑制化合物的影响、商业上有利的脂肪酸组成——所有这些都支持它们作为具有经济可行性的脂质原料的未来发展。在概述成功实施的各种策略以提高脂质和脂质衍生代谢物的生产的过程中，突出了代谢的独特方面，这些独特方面归因于它们的油脂特性。在某些产油酵母中积累脂质的大量计算机数据已经被精心整理，作为这些生物体具有特殊油脂特性的证据。在这些酵母中开发的执行这些策略的不同遗传元件被仔细检查，突出了新发现和合成构建的启动子、转录终止子和选择标记的主要类型。此外，还描述了大量先进的遗传工具箱和技术，这些技术近年来已成功用于产油酵母中，促进了同源重组、基因组编辑、DNA 组装和转化，效率显著提高。它们可以加速并有效地指导系统范围的代谢工程方法的合理设计，确定开发工业上适用的酵母菌株的关键目标。
