Enhanced α-ketoglutarate production in Yarrowia lipolytica WSH-Z06 by alteration of the acetyl-CoA metabolism.
α-Ketoglutarate (α-KG) is an important intermediate in the tricarboxylic acid (TCA) cycle and has an important role in the regulation of the balance between carbon and nitrogen metabolism in most microorganisms. In previous research, a thiamine-auxotrophic yeast for α-KG overproduction was screened and named as Yarrowia lipolytica WSH-Z06. To enhance α-KG production and reduce by-product (mainly pyruvate) accumulation, the cofactor metabolism was regulated to redistribute the carbon flux from pyruvate to α-KG. The acetyl-CoA synthetase gene, ACS1, from Saccharomyces cerevisiae and the ATP-citrate lyase gene, ACL, from Mus musculus were expressed to regulate the acetyl-CoA metabolism in Y. lipolytica WSH-Z06. The resultant strains were designated as Y. lipolytica-ACS1 and Y. lipolytica-ACL, respectively. Both of the ACS1 and ACL genes could increase the level of acetyl-CoA and enhance the α-KG production. In a 3-L jar fermenter, the highest yield of α-KG in Y. lipolytica-ACL reached up to 56.5 g L(-1) with an obvious decrease of pyruvate accumulation from 35.1 g L(-1) to 20.2 g L(-1). This study demonstrated that enhancing the acetyl-CoA availability could effectively increase the α-KG production in Y. lipolytica.
School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China. zhoujw1982@jiangnan.edu.cn
Jingwen
J
Zhou
Xiaoxia
X
Yin
Catherine
C
Madzak
Guocheng
G
Du
Jian
J
Chen
D001275:ATP Citrate (pro-S)-Lyase / Q000235:genetics / Q000378:metabolism; D000106:Acetate-CoA Ligase / Q000235:genetics / Q000378:metabolism; D000105:Acetyl Coenzyme A / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology; D005285:Fermentation; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D007656:Ketoglutaric Acids / Q000378:metabolism*; D008954:Models, Biological; D010957:Plasmids / Q000378:metabolism; D011995:Recombination, Genetic / Q000235:genetics; D015203:Reproducibility of Results; D025062:Yarrowia / Q000166:cytology / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*
D007656:Ketoglutaric Acids; D000105:Acetyl Coenzyme A; D001275:ATP Citrate (pro-S)-Lyase; D000106:Acetate-CoA Ligase