摘要
酿酒酵母是合成多种天然产物的微生物细胞工厂,合理利用酿酒酵母底盘细胞内源的代谢途径可生产高附加值的生物医药、食品保健和精细化学品类产物.如何精细调控和优化酿酒酵母胞内代谢流是实现目标化学物高产量、高产率和高转化的关键问题.乙酰辅酶A是中心代谢和天然产物合成的基本前体,精细调控乙酰辅酶A的合成是实现目标化合物高产的重要策略;改造酿酒酵母的甲羟戊酸途径,引入外源途径酶,表达萜类合成酶生产不同种类的萜类化合物;优化脂肪酸合成途径合成特定链长的脂肪酸及脂肪酸衍生物.本文总结了强化酿酒酵母中乙酰辅酶A积累的代谢工程策略,重构甲羟戊酸途径、脂肪酸途径从头合成天然萜类化合物和脂肪酸衍生物的研究进展,为利用酿酒酵母底盘细胞生产天然产物的相关研究提供代谢工程改造策略.
Saccharomyces cerevisiae acts as a bio-foundry for producing natural products.S.cerevisiae’s intrinsic pathways highlight microbial cell factories to produce pharmaceutics,food additive,and fine chemicals.For high-titer,yield,and conversion of target compounds,the critical point is that fine-tuning and optimizing intracellular metabolic flux in the yeast cell.Acetyl-CoA is the fundamental precursor for central metabolism and heterologous pathway.In comparison,acetyl-CoA compartmentalizes in mitochondria,nucleus,peroxisome subcellular,and cytosol.Most of the pathway enzymes are expressed in S.cerevisiae cytosol.So,we summarized the fine-tuning strategies of acetyl-CoA synthesis in cytosol matrix.The new acetyl-CoA pathway(phosphoketolase,phosphotransacetylase,and acetaldehyde dehydrogenase,PK/PTA-ADA)shows a high conversion ratio from the carbon source.The PK/PTA-ADA pathway presents improved redox balance,limited ATP requirement,and reduced carbon loss to CO2.Moreover,the heterologous ATP-dependent citrate lyase precisely converts mitochondria metabolism into acetyl-CoA.Knock-out acetyl-CoA depletion pathways retain high acetyl-CoA titer in the cytosol.The continuous metabolic engineering on PK/PTA-ADA pathway is expected for higher acetyl-CoA titer.The Mevalonate pathway has been engineered to produce terpenoids in S.cerevisiae.The exogenous HMG-CoA synthase and HMG-CoA reductase boost mevalonate pathway from acetyl-CoA.Further,the diversified terpenoids are generated from C5 unite Isopentenyl diphosphate and its’isomer dimethylallyl diphosphate.Intrinsic farnesyl diphosphate synthase(Erg20)shows both dimethylallyltransferase(geranyl diphosphate,C10 product)and geranyltransferase(farnesyl diphosphate,C15 product)activity.The F96W/N127W mutations in Erg20 caused steric hindrance for geranyl diphosphate substrate.So,geranyl diphosphate is accumulated to produce C10 terpenoids or meroterpenoids.Moreover,geranylgeranyl diphosphate synthase(CrtE)convert farnesyl diphosphate(C15)into geranylgeranyl diphosphate(C20
作者
张云丰
何丹
卢欢
黄建东
罗小舟
Yunfeng Zhang;Dan He;Huan Lu;Jiandong Huang;Xiaozhou Luo(CAS Key Laboratory for Quantitative Engineering Biology,Shenzhen Institute of Synthetic Biology,Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences(CAS),Shenzhen 518055,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2021年第3期310-318,共9页
Chinese Science Bulletin
基金
国家重点研发计划(2018YFA0903200)
中国博士后科学基金(2019M663184)
深圳市2020年基础研究面上项目(JCYJ20190807154003687)
广东省基础与应用研究基金(2019A1515110549)
深圳市科技创新委员会项目(KQTD2015033117210153)资助。
关键词
酿酒酵母
合成生物学
乙酰辅酶A
萜类
脂肪酸
Saccharomyces cerevisiae
synthetic biology
acetyl-CoA
terpenoid
fatty acid
