Metabolic engineering of Escherichia coli for the production of fumaric acid. Issue 7 (1st March 2013)

• Record Type: Journal Article
• Authors: Song, Chan Woo; Kim, Dong In; Choi, Sol; Jang, Jae Won; Lee, Sang Yup
• Is Part Of: Biotechnology and bioengineering. Volume 110:Issue 7(2013:Jul.)
• Page Start: 2025
• Page End: 2034
• Publication Date: 2013-03-01
• Subjects: Biotechnology -- Periodicals; Bioengineering -- Periodicals; 660.6
• DOI: 10.1002/bit.24868
• Languages: English
• ISSNs: 0006-3592

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Fumaric acid is a naturally occurring organic acid that is an intermediate of the tricarboxylic acid cycle. Fungal species belonging to <italic>Rhizopus</italic> have traditionally been employed for the production of fumaric acid. In this study, <italic>Escherichia coli</italic> was metabolically engineered for the production of fumaric acid under aerobic condition. For the aerobic production of fumaric acid, the <italic>iclR</italic> gene was deleted to redirect the carbon flux through the glyoxylate shunt. In addition, the <italic>fumA</italic>, <italic>fumB</italic>, and <italic>fumC</italic> genes were also deleted to enhance fumaric acid formation. The resulting strain was able to produce 1.45 g/L of fumaric acid from 15 g/L of glucose in flask culture. Based on in silico flux response analysis, this base strain was further engineered by plasmid‐based overexpression of the native <italic>ppc</italic> gene, encoding phosphoenolpyruvate carboxylase (PPC), from the strong <italic>tac</italic> promoter, which resulted in the production of 4.09 g/L of fumaric acid. Additionally, the <italic>arcA</italic> and <italic>ptsG</italic> genes were deleted to reinforce the oxidative TCA cycle flux, and the <italic>aspA</italic> gene was deleted to block the conversion of fumaric acid into <sc>L</sc>‐aspartic acid. Since it is desirable to avoid the use of inducer, the <italic>lacI</italic> gene was also deleted. To increase glucose uptake rate and fumaric acid productivity, the native promoter of the <italic>galP</italic> gene was replaced with the strong <italic>trc</italic> promoter. Fed‐batch culture of the final strain CWF812 allowed production of 28.2 g/L fumaric acid in 63 h with the overall yield and productivity of 0.389 g fumaric acid/g glucose and 0.448 g/L/h, respectively. This study demonstrates the possibility for the efficient production of fumaric acid by metabolically engineered <italic>E. coli</italic>. Biotechnol. Bioeng. 2013; 110: 2025–2034. © 2013 Wiley Periodicals, Inc.</p> </abstract>