A Soluble Chloroplast Protease Processes the Euglena Polyprotein Precursor to the Light Harvesting Chlorophyll a/b Binding Protein of Photosystem II


The Euglena light harvesting chlorophyll a/b binding protein of photosystem II (LHCPII) is synthesized as a polyprotein precursors composed of 8 LHCPIIs covalently joined by a decapeptide. A soluble chloroplast protease releases LHCPII from the polyprotein. The polyprotein processing peptidase has a pH optima between 8.0 and 9.0. It is inhibited by Zn2+, Cu2+, phenylmethylsulfonyl fluoride and E64 suggesting it is a novel thiol protease.

Publication Title

Plant and Cell Physiology