We engineered the Ferric Uptake Regulator (Fur) system to create an iron-responsive biosensor. The animations below demonstrate how the Fur protein binds iron to form a complex that binds to the Fur Box promoter sequence. Once Fur is bound to the promoter, it blocks transcription of the downstream gene.

• 1^st Plasmid with GFP
• 1^st Plasmid with LacI
• 2^nd Plasmid with GFP
• 2^nd Plasmid with LacI
• 3^rd Plasmid with GFP
• 3^rd Plasmid with EntA, EntD and EntF
• 3^rd Plasmid with EntB, EntC and EntE
• Control plasmid