S coding for photosystem-associated proteins have been duplicated in A. marina. Two of four unique copies of psbU (AM1 G0114 and AM1 D0138) are plasmidencoded, with a protein identity ranging from 36 to 82 . Both psaK and psbE share a conserved duplication found in many other cyanobacteria, with 32 and 68 identity, respectively. Last, all genes responsible for coding cytochrome b6f are present