View source for Part:BBa K3777021


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Basic biosensor device for erythromycin detection.

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<b><font size="3">Usage and Biology</font></b>
<br>The genetic circuit was composed of a coding sequence of  erythromycin repressor and ermc genes which was inserted into an expression vectors with a consitive promoter(BBa_J23114) and RBS(BBa_K3777030), as well as 3WJdB(BBa_K3777000) under the control of T7 promoter (BBa_K3777006).  The terminator we used were BBa_B0010 and BBa_M36305.(Fig 1)
<br>When tet was absent, TetR would bind to the inducible promoter（PI）and prevent RNA polymerase from initiating transcription, thus repressing the expression of reporter gene. If tet was present, TetR would no longer able to bind to the promoter, resulting in the expression of reporter gene.
<br>We expressed this circuit in the <i>E. coli </i> BL21(DE3) cells for tetracycline detection. Thus we could roughly deduce the concentration of the antibiotics in the sample according to the fluorescence intensity. 
https://static.igem.org/mediawiki/parts/thumb/3/3d/Tetr-tetO-3WJdB.PNG/799px-Tetr-tetO-3WJdB.PNG 
<br>                           Fig.1  Schematic overview of the genetic circuit.
<br><b><font size="3">Results</font></b>
<br>To verify the functionality of the biosensor, we performed a plate-reader experiment and measured optical density and fluorescence intensity every hour. We observed a correlation between concentration of antibiotics in the sample and intensity of fluorescent signal.

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<span class='h3bb'>Sequence and Features</span>
<partinfo>BBa_K3777021 SequenceAndFeatures</partinfo>


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===Functional Parameters===
<partinfo>BBa_K3777021 parameters</partinfo>
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