|Title||Plasmid-encoded protein attenuates E. coli swimming velocity and cell growth, not reprogrammed regulatory functions.|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Virgile, C, Hauk, P, Wu, H-C, Bentley, WE|
|Date Published||2019 Jan 21|
In addition to engineering new pathways for synthesis, synthetic biologists rewire cells to carry out 'programmable' functions, an example being the creation of wound-healing probiotics. Engineering regulatory circuits and synthetic machinery, however, can be deleterious to cell function, particularly if the 'metabolic burden' is significant. Here, a synthetic regulatory circuit previously constructed to direct E. coli to swim towards hydrogen peroxide, a signal of wound generation, was shown to work even with co-expression of antibiotic resistance genes and genes associated with lactose utilization. We found, however, that co-transformation with a second vector constitutively expressing GFP (as a marker) and additionally conferring resistance to kanamycin and tetracycline resulted in slower velocity (Δ ~6 μm/s) and dramatically reduced growth rate (Δ >50%). The additional vector did not, however, alter the run-and-tumble ratio or directional characteristics of H O -dependent motility. The main impact of this additional burden was limited to slowing cell velocity and growth, suggesting that reprogrammed cell motility by minimally altering native regulatory circuits can be maintained even when extraneous burden is placed on the host cell. This article is protected by copyright. All rights reserved.
|Alternate Journal||Biotechnol. Prog.|