TY - JOUR
T1 - Improving cellular malonyl-CoA level in Escherichia coli via metabolic engineering
AU - Zha, Wenjuan
AU - Rubin-Pitel, Sheryl B.
AU - Shao, Zengyi
AU - Zhao, Huimin
N1 - Funding Information:
This research was supported by a grant from the Office of Naval Research (N00014-02-1-0725). S. B. R.-P. acknowledges support from the National Institutes of Health Cell and Molecular Biology Training Grant Program and the National Science Foundation Graduate Research Fellowship Program.
PY - 2009/5
Y1 - 2009/5
N2 - Escherichia coli only maintains a small amount of cellular malonyl-CoA, impeding its utility for overproducing natural products such as polyketides and flavonoids. Here, we report the use of various metabolic engineering strategies to redirect the carbon flux inside E. coli to pathways responsible for the generation of malonyl-CoA. Overexpression of acetyl-CoA carboxylase (Acc) resulted in 3-fold increase in cellular malonyl-CoA concentration. More importantly, overexpression of Acc showed a synergistic effect with increased acetyl-CoA availability, which was achieved by deletion of competing pathways leading to the byproducts acetate and ethanol as well as overexpression of an acetate assimilation enzyme. These engineering efforts led to the creation of an E. coli strain with 15-fold elevated cellular malonyl-CoA level. To demonstrate its utility, this engineered E. coli strain was used to produce an important polyketide, phloroglucinol, and showed near 4-fold higher titer compared with wild-type E. coli, despite the toxicity of phloroglucinol to cell growth. This engineered E. coli strain with elevated cellular malonyl-CoA level should be highly useful for improved production of important natural products where the cellular malonyl-CoA level is rate-limiting.
AB - Escherichia coli only maintains a small amount of cellular malonyl-CoA, impeding its utility for overproducing natural products such as polyketides and flavonoids. Here, we report the use of various metabolic engineering strategies to redirect the carbon flux inside E. coli to pathways responsible for the generation of malonyl-CoA. Overexpression of acetyl-CoA carboxylase (Acc) resulted in 3-fold increase in cellular malonyl-CoA concentration. More importantly, overexpression of Acc showed a synergistic effect with increased acetyl-CoA availability, which was achieved by deletion of competing pathways leading to the byproducts acetate and ethanol as well as overexpression of an acetate assimilation enzyme. These engineering efforts led to the creation of an E. coli strain with 15-fold elevated cellular malonyl-CoA level. To demonstrate its utility, this engineered E. coli strain was used to produce an important polyketide, phloroglucinol, and showed near 4-fold higher titer compared with wild-type E. coli, despite the toxicity of phloroglucinol to cell growth. This engineered E. coli strain with elevated cellular malonyl-CoA level should be highly useful for improved production of important natural products where the cellular malonyl-CoA level is rate-limiting.
KW - Flavonoids
KW - Malonyl-CoA
KW - Metabolic engineering
KW - Polyketides
KW - Type III polyketide synthases
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U2 - 10.1016/j.ymben.2009.01.005
DO - 10.1016/j.ymben.2009.01.005
M3 - Article
C2 - 19558964
AN - SCOPUS:63649137435
SN - 1096-7176
VL - 11
SP - 192
EP - 198
JO - Metabolic Engineering
JF - Metabolic Engineering
IS - 3
ER -