Abstract
The production of l-tryptophan was investigated in a recombinant strain Escherichia coli W3110-ZDrr. It was observed that phosphate and feeding strategies are key factors to ensure the good cell growth and high production of l-tryptophan. The simple exponential feeding strategy could only produce 10.6 g/L l-tryptophan due to the improper feeding rate; while the manual glucose-feedback feeding approach could effectively control the substrate and inhibit the formation of acetate, and thus improvemed the l-tryptophan production to 25.5 g/L. The modified exponential feeding approach avoided overfeeding or underfeeding and achieved high production of l-tryptophan. Moreover, the addition of Tween 60 or PL61 could enhance the cell growth and the production of l-tryptophan in the fed-batch mode. Subsequent metabolic flux analysis showed that more carbon flux was distributed into the biosynthesis of l-tryptophan when Tween 60 or PL61 was supplied. The present work presents one base for further large-scale production of this important amino acid.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
