Differential sensitivities of the growth of Escherichia coli to acrylate under aerobic and anaerobic conditions and its effect on product formation
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The effect of acrylate on the growth of Escherichia coli was determined under aerobic and anaerobic conditions in glucose-defined medium. Growth occurred with up to 35 mM acrylate under aerobic conditions but ceased at 5 mM acrylate under anaerobic conditions. This differential sensitivity can be attributed to inhibition of pyruvate formate lyase and/or pflB gene repression, as this enzyme is necessary for anaerobic growth of E. coli. The effect of acrylate on end-product distribution was also determined by growing E. coli first aerobically, then switching to anaerobic conditions. In the absence of acrylate, E. coli generated the typical distribution of mixed-acid products, with about 12 % of pyruvate being metabolically converted to lactate. In contrast, in the presence of 5 mM acrylate, E. coli converted 83 % of pyruvate to lactate, consistent with a reduction in pyruvate formate lyase activity.
KeywordsAcrylate Aerobic/anaerobic effects E. coli Lactate Pyruvate formate lyase Pyruvate metabolism
- Burk MJ, Burgard AP, Pharkya P (2012) Microorganisms and methods for the biosynthesis of fumarate, malate, and acrylate U.S. Patent 8,129,154Google Scholar
- Kandasamy V, Vaidyanathan H, Djurdjevic I, Jayamani E, Ramachandran KB, Buckel W, Jayaraman G, Ramalingam S (2013) Engineering Escherichia coli with acrylate pathway genes for propionic acid synthesis and its impact on mixed-acid fermentation. Appl Microbiol Biotechnol 97:1191–1200PubMedCrossRefGoogle Scholar
- Lilga MA, White JR, Holladay JE, Zacher AH, Muzatko DS, Orth RJ (2010) Method for the conversion of β-hydroxy carbonyl compounds. U.S. Patent 7,687,661Google Scholar
- Zhong L, Whitehouse RS (2005) Methods of making intermediates from polyhydroxyalkanoates. U. S. Patent 6,897,338Google Scholar