代谢工程改造酿酒酵母发酵生产β-胡萝卜素OA北大核心CSTPCD

β-carotene,a member of the polyolefin family,is the predominant carotenoid found in fruits and vegetables.It possesses the ability to prevent and alleviate various diseases,such as heart disease,cataracts,and cancer.As a result,it is highly sought after in the market due to its potential health benefits.The potential for β-carotene production through biosynthesis holds promising prospects.Sig-nificantly,cytoplasmic acetyl coenzyme A is a crucial precursor for β-carotene synthesis,highlighting the importance of increasing its con-tent for efficient β-carotene production.In this study,the ATP-citrate lyase(ACL)from Aspergillus oryzae was introduced into the starter strain Saccharomyces cerevisiae ZS20,in which the CAB1 gene was also overexpressed,to increase the cytoplasmic acetyl-coenzyme A con-tent.As a result,the β-carotene production significantly increased,reaching 333.3 mg/L in the flask fermentation of strain L5,which was a 2.1-fold increase compared to the starter strain.To further enhance the yield of β-carotene production,strain L5 was utilized to comple-ment the deficient key genes responsible for adenine,lysine,leucine,and tryptophan synthesis,resulting in the development of strain L11.Initially,strain L11 demonstrated a β-carotene yield of 378.1 mg/L when cultivated in shaking flasks.Subsequently,through addi-tional optimization of the fermentation process carried out in the fermenter,the yield was significantly enhanced to 1 152.7 mg/L.