Team:KULeuven/Modeling/Key Antikey

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Contents

Key Lock Antikey

Overview

The Key and Antikey system performs a subtraction of the blue light signal and the vanillin receptor signal. The result controls the vanillin production. The biology behind the subtraction involves the annealing of complementary RNA strands, the Key and the Antikey. This reaction is favoured over the reaction between the Key and the Lock leading to vanillin synthesis. In this way we try to perform the subtraction before inducing production of vanillin.

This biological equivalent of a subtraction can only yield a positive number, so one can only subtract a small from a big amount. Because we can only actively produce vanillin, we have to subtract the measured quantity of vanillin, the amount of anti-key produced by the vanillin receptor from the wanted quantity of vanillin, the amount of key produced by the blue light sensor.

Models

Comparator.png

Simulation

Simulations were conducted to investigate the input output behaviour of the key lock system. In the figures that follow time is measured in seconds and quantities in molecules.

In the figure below the blue light input is represented in blue, the vanillin input is green, the amount of unlocked key is represented in blue.

Key antikey.png

Because of the nonlinear relationship between input and (anti)key (Michaelis-Menten), the steady state level of key depends on the level of both blue light sensor and vanillin sensor input and not just the difference between the two.

The most important conclusion is that for good functioning of the differentiator the transcription of both the key and the antikey are operated in the linear region.