Development of an autonomous and bifunctional quorum-sensing circuit for metabolic flux control in engineered Escherichia coli
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25562.full.pdf
Description
Published version
Size
1.02 MB
Format
Adobe PDF
Checksum (MD5)
db83c040c2e8975c456bcafca386023c
Author(s)
Dinh, Christina V.
Prather, Kristala L. Jones
Date Issued
December 3, 2019
Journal
Proceedings of the National Academy of Sciences of the United States of America
Publisher
Proceedings of the National Academy of Sciences
Citation
Dinh, Christina V. and Kristala L. J. Prather. "Development of an autonomous and bifunctional quorum-sensing circuit for metabolic flux control in engineered Escherichia coli." Proceedings of the National Academy of Sciences of the United States of America 116 (2019): 25562-25568 © 2019 The Author(s)
Version
Final published version
Abstract
Metabolic engineering seeks to reprogram microbial cells to efficiently and sustainably produce value-added compounds. Since chemical production can be at odds with the cell’s natural objectives, strategies have been developed to balance conflicting goals. For example, dynamic regulation modulates gene expression to favor biomass and metabolite accumulation at low cell densities before diverting key metabolic fluxes toward product formation. To trigger changes in gene expression in a pathway-independent manner without the need for exogenous inducers, researchers have coupled gene expression to quorum-sensing (QS) circuits, which regulate transcription based on cell density. While effective, studies thus far have been limited to one control point. More challenging pathways may require layered dynamic regulation strategies, motivating the development of a generalizable tool for regulating multiple sets of genes. We have developed a QS-based regulation tool that combines components of the lux and esa QS systems to simultaneously and dynamically up- and down-regulate expression of 2 sets of genes. Characterization of the circuit revealed that varying the expression level of 2 QS components leads to predictable changes in switching dynamics and that using components from 2 QS systems allows for independent tuning capability. We applied the regulation tool to successfully address challenges in both the naringenin and salicylic acid synthesis pathways. Through these case studies, we confirmed the benefit of having multiple control points, predictable tuning capabilities, and independently tunable regulation modules.
Subjects
Multidisciplinary
MIT Department
Massachusetts Institute of Technology. Department of Chemical Engineering
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
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DOI of Published Version
https://doi.org/10.1073/pnas.1911144116
