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Orthogonal Test in silico

Our Luminesensor is expected to be orthogonal to endogenous SOS pathway. In order to remove this obstacle on the application prospects of our Luminesensor, we use LexA408 instead of the wild-type LexA. LexA408 and LexA are bio-orthogonal with each other since the sequence of the binding sites have variations (See Characterization).

Figure 10 <i>Luminesensor</i> LexA408-VVD

Figure 10. Moecular Modeling for Luminesensor LexA408-VVD.

By adding several nodes into the network, we constructed modeling for orthogonality test:

Figure 11

Figure 11. Kinetic Network for Orthogonal Analysis


  • L denotes Luminesensor
  • I denotes the inner wild LexA
  • DL denotes the specific DNA binding site to Luminesensor
  • DI denotes the specific DNA binding site to wild LexA

The parameters are estimated as following:

k61.x10-4s-1dimered LexA releasing rate constant from non-specific binding site
K61.x10-2(n mol/L)-1dimered non-specific binding equilibrium constant

Tab 2. Reaction Parameters for Orthogonal Test

Figure 12

Figure 12. Orthogonal Test Result.

The result shows that the contrast is highly related to the orthogonality. As our Luminesensor is orthogonal to the endogerous LexA system, our system still works well in bacteria with endogenous LexA (See Characterization).


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