Engineered device in E. coli lyses S. aureus at physiological fever temperatures

Multiple strains of Staphylococcus are resistant to antibiotics, including the well-known methicillin-resistant Staphylococcus aureus (MRSA). We share an engineered plasmid device in Escherichia coli that lyses the disease-causing pathogen, S. aureus. The device was engineered using BioBrick parts obtained from the International Genetically Engineered Machine foundation (iGEM). The cI-blue-lysostaphin device consists of a temperature-sensitive promoter that is activated under physiological fever temperatures above 35°C that drives expression of a blue chromoprotein reporter and mature truncated lysostaphin enzyme. The functioning cI-blue-lysostaphin device was tested for optimal lysis conditions in MM294 and DH5α E. coli chassis and across incubation temperatures ranging from 30-42°C. We conclude that the lysostaphin activity of the cI-blue-lysostaphin device differs between chassis and increases with greater incubation temperature.