Expression and characterization of the calcium-activated photoprotein from the ctenophore Bathocyroe fosteri: Insights into light-sensitive photoproteins

► We have expressed and characterized the first photoprotein from Bathocyroe fosteri. ► Emission spectra of BfosPP was at the upper limit of previous in vivo observations. ► This photoprotein is inactivated when exposed to certain wavelengths of light. ► There are non-conservative substitutions in the putative binding-pocket of ctenophores.