Strains
HT strain is E. coli MG1655 strain transformed with both pBGT and pBRT plasmids. pBGT plasmid carries the ampicillin resistance gene blaTEM1, eGFP gene under the arabinose promoter and the araC represor. pBRT plasmid is derived from the pBGT plasmid but the bla gene is interchanged for the blaTEM12 variant which confers resistance to CAZ, and the eGFP gene is replaced by the  DsRed fluorescent protein gene. A monocopy of both resistance and reporter genes were introduced in the chromosome into another MG1655, namely MG1655::TEM1GFP and MG1655::TEM12DsRed