From 2009.igem.org
Vanillin Sensor
The vanillin receptor senses the vanillin concentration outside the cell. This information is needed to create the feedback loop in order to control vanillin synthesis. When the sensor senses vanillin a protein, virA, binds a phosphor. Afterwards virA gives the phosphor to an other protein, virG. VirG, with phosphor, in turn binds on a vir box triggering transcription. this way the transcribed component is proportional to the concentration of vanillin.
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