Figure 1
From: Structural studies of the mechanism for biosensing antibiotics in a fluorescein-labeled β-lactamase
Biosensing of β-lactam antibiotics by fluorescein-labelled PenP. (a) De-convoluted ESI mass spectrum of PenP-E166Cf. The add-up at the bottom confirms the correct mass of the labelled protein. (b) Fluorescence scanning spectra of PenP-E166Cf in the presence of 10-5M cefotaxime in 50 mM phosphate buffer (pH 7.0). (c) Change in fluorescence emission of PenP-E166Cf after incubation with different antibiotics (cefotaxime, ceftriaxone, ceftazidime, cephaloridine, cephalothin, cefoxitin, cefuroxime, penicillin G and ampicillin) at 10-6 M for 100 s. (d) Time-dependent fluorescence spectra in the presence of different concentrations (1 × 10-8 M - 1 × 10-5 M) of cefotaxime monitored at 515 nm.