De novo Genome Sequence of Roseibium alexandrii MAR44 Strain, a Marine Bacterium with Capacity to Synthesize PHA Bioplastics and a Photosynthesis Gene Cluster

We report here the genome sequence of Roseibium alexandrii strain MAR44, an alpha-proteobacterium isolated from an experimental device to monitor bioplastics colonization in the Mediterranean Sea. The genome assembly comprises a total of 5.25 Mb with a GC content of 56.33% and 5,019 predicted genes. Genome annotation reveals that MAR44 strain contains several pha genes involved in the polymerisation and depolymerisation of polyhydroxyalkanoates; phaA , phaB and phaC encode for the enzymes responsible of the last steps of the biosynthetic pathway, whereas phaZ encodes for a PHA-depolymerase. We also identified the phaR regulator and four phaP genes encoding for phasin proteins with a role in folding and accumulation of PHA in subcellular granules. In addition, we identified a photosynthesis gene cluster including the bch genes for the bacteriochlorophyll a synthesis and the puf operon encoding photosynthetic reaction centre and light-harvesting genes. In another manuscript we describe the efficient production of PHA by this strain under different conditions of carbon source supplementation and photosynthetic light.