Time-resolved fluorescence spectra of WasCFP.
(a) Emission decay contour plots of WasCFP at various pH. The difference between the neighboring lines corresponds to the constant intensity difference on a logarithmic scale. Red color corresponds to higher intensities. (b) Fluorescence decay curves of WasCFP detected at 510 nm under 372 nm or 467 nm excitation in solutions with various pH.