AUTHOR=Yu Shiqin , Plan Manuel R. , Winter Gal , Krömer Jens O. 

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

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=4

YEAR=2016

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2016.00090

DOI=10.3389/fbioe.2016.00090

ISSN=2296-4185

ABSTRACT=<p><italic>para</italic>-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. <italic>Pseudomonas putida</italic> KT2440 was engineered to produce PHBA from glucose <italic>via</italic> the shikimate pathway intermediate chorismate. To obtain the PHBA production strain, chorismate lyase UbiC from <italic>Escherichia coli</italic> and a feedback resistant 3-deoxy-<sc>d</sc>-arabino-heptulosonate-7-phosphate synthase encoded by gene <italic>aroG</italic><sup>D146N</sup> were overexpressed individually and simultaneously. In addition, genes related to product degradation (<italic>pobA</italic>) or competing for the precursor chorismate (<italic>pheA</italic> and <italic>trpE</italic>) were deleted from the genome. To further improve PHBA production, the glucose metabolism repressor <italic>hexR</italic> 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<sup>−1</sup> and a carbon yield of 18.1% (C-mol C-mol<sup>−1</sup>) in a non-optimized fed-batch fermentation. This is to date the highest PHBA concentration produced by <italic>P. putida</italic> using a chorismate lyase.</p>