Complete genome sequence of a marine bacterium with two chromosomes, Pseudoalteromonas translucida KMM 520(T)

Bacteria with multiple chromosomes provide new insights into the evolution of multipartite genome structures and bacterial survival strategies. In this study, we report the complete genome sequence of Pseudoalteromonas translucida KMM 520(T), which contains two circular chromosomes and comprises 4,147,593 bp with a mean G+C content of 40.1%. The two chromosomes have similar G+C contents and similar percentages of coding regions. Chromosome II of P. translucida possesses a plasmid-type replication initiator protein (RepA), which indicated that chromosome II is probably originated from a plasmid. COG functional categories revealed that the two chromosomes have divergent distributions of functional categories, which indicated that they bear different responsibilities for cellular functions. The complete genome sequence of P. translucida contributes to a better understanding of the origin and evolution of the additional chromosome and the physiology of Pseudoalteromonas genus.