挥发性脂肪酸（VFAs）平台是继糖平台之后提出的新型生物能源开发平台，基于VFAs平台的微生物油脂合成也成为了一个新的研究领域。粘红酵母在基于糖平台的油脂合成中显示了优良的特性，而基于VFAs平台的底物代谢及油脂合成亟待研究。申请者选育了一株高产油脂的粘红酵母菌株，并对该菌株代谢不同底物合成油脂开展了大量研究工作。本项目拟在前期工作基础上，研究乙酸、丙酸、丁酸对粘红酵母细胞生长及油脂合成的影响，探讨粘红酵母对不同VFAs的耐受性及代谢差异；通过研究VFAs转化过程中粘红酵母乙酰辅酶A羧化酶和二酯酰甘油酰基转移酶转录表达差异、辅酶及电子流的变化，解析VFAs对油脂合成关键酶的影响；通过过量表达粘红酵母ACC和DGA基因，解析VFAs代谢过程中乙酰辅酶A的代谢分配特征。相关研究成果可深化对粘红酵母VFAs代谢机理的认识，并为基于VFAs平台生产微生物油脂的进一步菌种改造及工艺优化提供理论指导。

Following the sugar platform, volatile fatty acids (VFAs) became a new platform for biofuels production in recent years. Lipid synthesis based on VFAs platform turned into a new research area. Rhodotorula glutinis showed excellent performance in the lipid synthesis based on sugar platform, while lipid synthesis based on VFAs platform by Rhodotorula glutinis still need to be explored. A Rhodotorula glutinis strain with high lipid producing ability has been developed and lipid production with different substrates has been studied by the applicant. This project scheduled to study the effect of acetic acid, propionic acid and butyric acid on the cell growth and lipid production, discuss the metabolism difference and VFAs tolerance of Rhodotorula glutinis. The transcription and expression difference of Acetyl-CoA carboxylase and diester acyl glycerol acyltransferase,the coenzyme and electron flow variation with different VFAs as substrates will be compared to explain the effect of VFAs on the key enzyme of lipid synthesis by Rhodotorula glutinis. The distribution characteristic of Acetyl-CoA also will be studied with ACC and DGA gene overexpression. The results will be useful for the deep understanding on the metabolism of lipid synthesis by Rhodotorula glutinis with VFAs and it also helpful for the further strain development and fermentation the coenzyme and electron flow variation with different VFAs as substrates will be compared to explain the effect of VFAs on the key enzyme of lipid synthesis by Rhodotorula glutinis. The distribution characteristic of Acetyl-CoA also will be studied with ACC and DGA gene overexpression. The results will be useful for the deep understanding on the metabolism of lipid synthesis by Rhodotorula glutinis with VFAs and it also helpful for the further strain development and fermentation optimization. with VFAs and it also helpful for the further strain development and fermentation optimization.