CHLOROPHYLL BINDING ABILITIES OF PLANTS WSCP AND DUF538 PROTEINS: THE POSSIBILITY OF COVALENT LINKS

Studies on plants hydrophobic WSCP (water soluble chlorophyll binding proteins) are the recent challenges involved in chlorophyll metabolism and biological concerns. We newly identified that plants DUF538 (domain of unknown function 538) proteins are the non-chloroplastic functional homologues of class 1 WSCP. Presently, by using computational bioinformatics tools, the molecular interactions between WSCP1 / DUF538 proteins and Chl a / Chl b were separately investigated. The results showed that DUF538 has the more affinity towards chlorophyll molecules as compared to WSCP. It was predicted that the aspartic acid residues 78 and 71 of DUF538 protein could be involved in its covalent interaction with Chl a and Chl b molecules, respectively. The difference between binding capacities, may furthermore confirm the important role of cytosolic proteins with regard to chlorophyll metabolism in plants.