Intrinsic photoisomerization dynamics of protonated Schiff-base retinal

Abstract

The primary photoresponse of protonated Schiff-base retinal in visual and bacterial rhodopsins is fast sub-ps isomerisation. Here, the authors show that the fast photoisomerization of rhodopsin is related to an intrinsic retinal property, whereas bacterial rhodopsins tune the excited-state potential-energy surface and improve the isomerization timescale and specificity.