Team:Tec-Chihuahua/ModifiedCell
MODIFIED CELL
aiiA: UNREGULATED GENE RESPONSIBLE FOR QUORUM SENSING INHIBITION
After studying the wild cell behavior, one of our solutions to turn off its virulence was to genetically modify Erwinia amylovora. We introduced a gene that codifies to an AHL degrading enzyme, AHL-lactonase (aiiA). In bacterial pathogens, this enzyme disrupts bacterial quorum sensing, consequently inhibiting the production of pathogenesis factors.
In this modified bacteria, the aiiA gene (green rectangle) codifies to our antidote protein (green oval) in an unregulated manner. After some time, the protein production will reach a constant production big enough to act on the quorum sensing regulation. With a constitutive aiiA expression, we expect a complete and uninterrupted inhibition of the AHLs activity by hydrolyzing them and varying the lengths of their acyl chains, modifying their conformational structure. Therefore its autoregulation will be unable to be completed, resulting in no more AHL production.
To model the behavior of this gene inside Erwinia amylovora, we first came to several assumptions discussed below.
References
Barnard, A. and Salmond, G. (2006) Quorum sensing in Erwinia species. Analytical and Bioanalytical Chemistry, 387(2), pp.415-423.
Frederick K. Balagaddé et al. (2008) A synthetic Escherichia coli predator–prey ecosystem, EMBO, 187, pp. 1-26.
Ingalls, B. (2013) Modeling of Chemical Reaction Networks & Gene Regulatory Networks. From Mathematical Modeling in Systems Biology(pp. 21-314 ). England: MIT press.
James, S. et al. (2000) Luminescence Control in the Marine Bacterium Vibrio fischeri: An Analysis of the Dynamics of lux Regulation., JMB, 296, pp. 1127-1137.
Koczan JM, McGrath MJ, Zhao Y, Sundin GW (2009) Contribution of Erwinia amylovora exopolysaccharides amylovoran and levan to biofilm formation: implications in pathogenicity. Phytopathology 99:1237-1244
Tzvia Iljon, Jenna Stirling and Robert J.Smith (2012) A mathematical model describing an outbreak of fire blight. En Understanding the Dynamics of Emerging and Re-Emergign Infectious Diseases Using Mathematical Models(91-104). University of Ottawa, Canada: Transworld Research Network.
Venturi, V., Venuti, C., Devescovi, G., Lucchese, C., Friscina, A., Degrassi, G., Aguilar, C. and Mazzucchi, U. (2017) The plant pathogen Erwinia amylovora produces acyl-homoserine lactone signal molecules in vitro and in planta.
