产油酵母的研究现状与展望

Research Progress and Prospect of Oleaginous Yeast

生物能源是从生物来源的材料制成的可再生能源,主要分为生物质能、生物燃料、生物气体三大类,具有绿色、低碳、清洁、可再生等优点.微生物油作为第三代生物柴油,有可能成为传统化石燃料的绿色替代品,是缓解能源挑战和环境问题的研究热点.本文综述产油酵母油脂合成与调控机制以及代谢工程等研究进展.产油酵母作为微生物油生产的主体,其异柠檬酸脱氢酶的活性依赖一磷酸腺苷(AMP),使得它们在限氮条件下大量积累油脂;酵母积累油脂受到各种条件的影响(比如碳氮源、温度、溶氧、pH值等),相关碳氮源利用与胁迫调控转录因子GAT1、MIG1、ASG1、MYB、GRAS、CBF11、TORC1 bHLH8和PHD等也调控其脂代谢.但产油酵母相对于酿酒酵母来说,其油脂合成机制与遗传背景依旧不清晰,限制了其工业化应用.因此,未来还需要加强微生物油生产技术的研究,从提高菌株鲁棒性、增加经济性代谢副产物产量、提高廉价底物利用能力等方面降低微生物油的生产成本,使其成为传统化石燃料的有效替代品.

With the advantages of being green,low-carbon,clean,and renewable,bioenergy is a form of energy that is produced from biologically based materials.It is primarily divided into three categories:biomass,biofuel,and biogas.In light of their potential to replace conventional fossil fuels with a greener alternative,microbial oils,the third generation of biodiesel,have gained attention as a focus of study to address energy and environmental issues.This paper reviews the progress of research on lipid synthesis,regulation mechanisms,and metabolic engineering in oleaginous yeast,which is the mainstay of microbial lipid production and whose isocitrate dehydrogenase activity is dependent on adenosine monophosphate(AMP),allowing them to accumulate large amounts of lipids under nitrogen-limiting conditions.Because various conditions(e.g.,carbon and nitrogen sources,temperature,dissolved oxygen,pH,etc.)affect lipid accumulation,the related carbon and nitrogen source utilization and stress-regulated transcription factors,GAT1,MIG1,ASG1,MYB,GRAS,CBF11,TORC1 bHLH8,and PHD,among others,also regulate lipid metabolism in oleaginous yeast.However,unlike Saccharomyces cerevisiae,the lipid synthesis process and genetic background of oleaginous yeasts are still unknown,limiting their potential for industrial application.As a result,several studies will be needed in the future to develop technologies for microbial lipid production in terms of improving strain robustness,increasing the production of economical metabolic by-products,and improving the ability to utilize economical substrates,so that it can become an effective alternative to traditional fossil fuels.