Complete genome of Pelagovum pacificum SM1903 isolated from the marine surface oligotrophic environment.

Pelagovum pacificum SM1903, belonging to a novel genus of the family Rhodobacteraceae, was isolated from the surface seawater of the Mariana Trench. Here, we report the first complete genome sequence of the novel genus Pelagovum. The genome of strain SM1903 consists of a circular chromosome of 4,040,866 bp and two plasmids of 41,363 bp and 9705 bp, respectively. Gene annotation and metabolic pathway analyses showed that strain SM1903 possesses a series of genes related to adaptation to marine oligotrophic environments, which are involved in utilization of aromatic compounds, allantoin, and alkylphosphonate, and second messenger signaling in response to the oligotrophic stress. This strain also contains a variety of genes involved in coping with other stresses including osmotic stress, oxidative stress, cold shock, and heat shock. These features would assist this strain to survive under the natural nutrient limitation and other stresses from the environment. The genome of strain SM1903 of the novel genus Pelagovum would deepen our knowledge on marine bacterioplankton and their adaption strategies to marine oligotrophic environments.