Dual regulation of lipid droplet-triacylglycerol metabolism and ERG9 expression for improved ß-carotene production in Saccharomyces cerevisiae.
Microb Cell Fact
; 21(1): 3, 2022 Jan 04.
Article
em En
| MEDLINE
| ID: mdl-34983533
ABSTRACT
BACKGROUND:
The limitation of storage space, product cytotoxicity and the competition for precursor are the major challenges for efficiently overproducing carotenoid in engineered non-carotenogenic microorganisms. In this work, to improve ß-carotene accumulation in Saccharomyces cerevisiae, a strategy that simultaneous increases cell storage capability and strengthens metabolic flux to carotenoid pathway was developed using exogenous oleic acid (OA) combined with metabolic engineering approaches.RESULTS:
The direct separation of lipid droplets (LDs), quantitative analysis and genes disruption trial indicated that LDs are major storage locations of ß-carotene in S. cerevisiae. However, due to the competition for precursor between ß-carotene and LDs-triacylglycerol biosynthesis, enlarging storage space by engineering LDs related genes has minor promotion on ß-carotene accumulation. Adding 2 mM OA significantly improved LDs-triacylglycerol metabolism and resulted in 36.4% increase in ß-carotene content. The transcriptome analysis was adopted to mine OA-repressible promoters and IZH1 promoter was used to replace native ERG9 promoter to dynamically down-regulate ERG9 expression, which diverted the metabolic flux to ß-carotene pathway and achieved additional 31.7% increase in ß-carotene content without adversely affecting cell growth. By inducing an extra constitutive ß-carotene synthesis pathway for further conversion precursor farnesol to ß-carotene, the final strain produced 11.4 mg/g DCW and 142 mg/L of ß-carotene, which is 107.3% and 49.5% increase respectively over the parent strain.CONCLUSIONS:
This strategy can be applied in the overproduction of other heterogeneous FPP-derived hydrophobic compounds with similar synthesis and storage mechanisms in S. cerevisiae.Palavras-chave
Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Saccharomyces cerevisiae
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Farnesil-Difosfato Farnesiltransferase
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Triglicerídeos
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Regulação Fúngica da Expressão Gênica
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Beta Caroteno
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Proteínas de Saccharomyces cerevisiae
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Gotículas Lipídicas
Idioma:
En
Revista:
Microb Cell Fact
Ano de publicação:
2022
Tipo de documento:
Article