Authors: Naoko Okai Takanori Miyoshi Yasunobu Takeshima Hiroaki Kuwahara Chiaki Ogino Akihiko Kondo
Publish Date: 2015/09/21
Volume: 100, Issue: 1, Pages: 135-145
Abstract
Protocatechuic acid 34dihydroxybenzoic acid PCA serves as a building block for polymers and pharmaceuticals In this study the biosynthetic pathway for PCA from glucose was engineered in Corynebacterium glutamicum The pathway to PCAemployed elements of the chorismate pathway by using chorismatepyruvate lyase CPL and 4hydroxybenzoate hydroxylase 4HBA hydroxylase As C glutamicum has the potential to synthesize the aromatic amino acid intermediate chorismate and possesses 4HBA hydroxylase we focused on expressing Escherichia coli CPL in a phenylalanineproducing strain of C glutamicum ATCC21420 To secrete PCA the gene ubiC encoding CPL from E coli was expressed in C glutamicum ATCC 21420 strain FUbiC The formation of 288 mg/L of extracellular 4HBA 36 h and 213 ± 29 mg/L of extracellular PCA 80 h was obtained by the C glutamicum strain FUbiC from glucose The strain ATCC21420 was also found to produce extracellular PCA PCA fermentation was performed using C glutamicum strain FUbiC in a bioreactor at the optimized pH of 75 C glutamicum FUbiC produced 615 ± 21 mg/L of PCA from 50 g/L of glucose after 72 h Further fedbatch fermentation of PCA by C glutamicum FUbiC was performed with feedings of glucose every 24 h The maximum production of PCA 11400 ± 116 mg/L was achieved when 1170 g/L of glucose was added over 96 h of fedbatch fermentationThis work was partially supported by Special Coordination Funds for Promoting Science and Technology Creation of Innovation Centers for Advanced Interdisciplinary Research Areas Innovative Bioproduction Kobe from the Ministry of Education Culture Sports Science and Technology of Japan We appreciate help from Drs Fumio Matsuda Fumiyoshi Okazaki Satoshi Wakai and Shimpei Aikawa for discussions regarding this work We thank Ms Michiru Miyake for technical assistance
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