Effects of aroP gene disruption on L-tryptophan fermentation

Abstract

The production of L-tryptophan through chemical synthesis, direct fermentation, bioconversion and enzymatic conversion has been reported. However, the role of the transport system for the aromatic amino acids in L-tryptophan producing strains has not been fully explored. In this study, the aroP gene of the L-tryptophan producing Escherichia coli TRTH strain was disrupted using Red recombination technology and an aroP mutant E. coli TRTH ΔaroP was constructed. Fed-batch fermentation of E. coli TRTH ΔaroP was carried out in 30-L fermentor to investigate the L-tryptophan production. Compared with E. coli TRTH, the aroP mutant was able to maintain a higher growth rate during the exponential phase of the fermentation and the L-tryptophan production increased by 13.3%.

Key words： Escherichia coli TRTH; aroP; L-tryptophan fermentation; Red recombination

Acknowledgments

This work was supported by the program for Changjiang Scholars and Innovative Research Team in University of China (IRT1166).

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