Induction of pSEVA237M-based bioreporters in P. putida mt-2 under matric stress. Bioreporter cells were exposed to mild matric stress of −0.5 MPa or extensive matric stress of −1.5 MPa, and fluorescence was detected by flow cytometry. Data are mean values ± S.D. (n = 3) of average fluorescence intensity of cells incubated under matric stress of −0.5 MPa or −1.5 MPa normalized to the average fluorescence intensity of Ctrl cells. Asterisks (*) indicate mean values from treated cultures that are significantly (P < 0.05) higher than mean values from Ctrl cultures.