Is the photoactive yellow protein a UV-B/blue light photoreceptor?

Abstract

UV light below 300 nm is shown to generate the first photocycle intermediate in the blue light photoreceptor Photoactive Yellow Protein. Fluorescence and ultrafast transient absorption measurements indicate two excitation pathways: UV-B absorption by the chromophore and Fluorescence Resonant Energy Transfer (FRET) from tryptophan and tyrosine residues.