This model represents the reductase which acts reduces the geranylgeranyl group to the phytyl group in the side chain of chlorophyll. It is unclear whether the enzyme has a preference for acting before or after the attachment of the side chain to chlorophyllide a by chlorophyll synthase. This clade is restricted to plants and cyanobacteria to separate it from the homologues which act in the biosynthesis of bacteriochlorophyll. [Biosynthesis of cofactors, prosthetic groups, and carriers, Chlorophyll and bacteriochlorphyll]
Jiyao W et al.(2023). "The conserved domain database in 2023.",