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From 2012hs.igem.org

Abstract

Silver nanoparticles (AgNP’s) have a variety of beneficial health effects but can be detrimental to both human and environmental health in excessive quantities. As a result, NCSSM iGEM has attempted to develop an inexpensive biosensor for detecting AgNP’s in vivo. This novel AgNP biosensor utilizes ACE1, a silver binding transcription factors from S. cerevisiae (yeast), in an E. coli chassis. In the biosensor’s synthetic gene network, a constitutive promoter upstream of ACE1 ensures continuous expression of the ACE1 protein. In the presence of AgNP’s, ACE1 activates the CUP1 promoter which has been placed upstream of a Green Fluorescent Protein gene. Subsequently, exposure of the E. coli biosensor to AgNP’s will result in high levels of GFP expression. Network success was confirmed in vivo by spreading the biosensor on plates containing varying concentrations of AgNP’s. However, due to the antimicrobial effects of AgNP’s, network success under high AgNP concentrations remains unconfirmed.