Team:NEFU China/fit
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
Yogurt can easily get bacteria contamination when improperly stored. We generally cannot determine whether a cup of yogurt is safe for eating just through checking its appearance, so we asked this question: can we make spoiled yogurt look different?
This year, the iGEM team of NEFU_China aims at creating a novel and handy method for the detection of pathogens in yogurt. Autoinducer2 (AI-2), a signal molecule constantly produced by pathogens in yogurt, serves as the key in our project. We cloned genes related to the AI-2 responsive pathway in Salmonella typhimurium and integrated them into the genome of Lactobacillus bulgaricus. Our engineered Lactobacillus will be able to uptake AI-2 molecules from pathogens and trigger the expression of a report gene that produces a blue pigment. Since our engineered Lactobacillus can act as an auxiliary starter in yogurt fermentation, the detecting process can be greatly simplified. If you open a cup of yogurt and find it has already turned blue, you can just trash it.