The family of the xanthopsins is the photoreceptor family that carries trans-p-coumaric acid, through a thiol-ester linkage, as its light-sensitive chromophore. It is sensitive to yellow light. PYP di...The family of the xanthopsins is the photoreceptor family that carries trans-p-coumaric acid, through a thiol-ester linkage, as its light-sensitive chromophore. It is sensitive to yellow light. PYP displays a typical R/β fold, with a central five-stranded β-sheet and helical segments on either side, which has become the prototype for the PAS domain, a key element in biological signal transfer.
