Metabolic Engineering of Pseudomonas putida KT2440 for the Production of para-Hydroxy Benzoic Acid

Shiqin Yu; Manuel R Plan; Gal Winter; Jens O Krömer

doi:10.3389/fbioe.2016.00090

Metabolic Engineering of Pseudomonas putida KT2440 for the Production of para-Hydroxy Benzoic Acid

Front Bioeng Biotechnol. 2016 Nov 28:4:90. doi: 10.3389/fbioe.2016.00090. eCollection 2016.

Authors

Shiqin Yu¹, Manuel R Plan², Gal Winter³, Jens O Krömer¹

Affiliations

¹ Centre for Microbial Electrochemical Systems (CEMES), The University of Queensland, Brisbane, QLD, Australia; Advanced Water Management Centre (AWMC), The University of Queensland, Brisbane, QLD, Australia.
² Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD, Australia; Metabolomics Australia (Queensland Node), The University of Queensland, Brisbane, QLD, Australia.
³ Centre for Microbial Electrochemical Systems (CEMES), The University of Queensland, Brisbane, QLD, Australia; Advanced Water Management Centre (AWMC), The University of Queensland, Brisbane, QLD, Australia; School of Science and Technology, The University of New England, Armidale, NSW, Australia.

Abstract

para-Hydroxy benzoic acid (PHBA) is the key component for preparing parabens, a common preservatives in food, drugs, and personal care products, as well as high-performance bioplastics such as liquid crystal polymers. Pseudomonas putida KT2440 was engineered to produce PHBA from glucose via the shikimate pathway intermediate chorismate. To obtain the PHBA production strain, chorismate lyase UbiC from Escherichia coli and a feedback resistant 3-deoxy-d-arabino-heptulosonate-7-phosphate synthase encoded by gene aroG^D146N were overexpressed individually and simultaneously. In addition, genes related to product degradation (pobA) or competing for the precursor chorismate (pheA and trpE) were deleted from the genome. To further improve PHBA production, the glucose metabolism repressor hexR was knocked out in order to increase erythrose 4-phosphate and NADPH supply. The best strain achieved a maximum titer of 1.73 g L^-1 and a carbon yield of 18.1% (C-mol C-mol^-1) in a non-optimized fed-batch fermentation. This is to date the highest PHBA concentration produced by P. putida using a chorismate lyase.

Keywords: Pseudomonas putida KT2440; metabolic engineering; para-hydroxy benzoic acid; shikimate pathway.