The research, published today as a Reviewed Preprint in eLife, is described by the editors as an important study that advances our understanding of physiological mechanisms in deep-sea Planctomycetes bacteria, revealing unique characteristics such as being the only known species in the class of Phycisphaerae bacteria that uses a distinct budding model of division. It provides what the editors also say is convincing evidence that the new species is extensively involved in nitrogen assimilation and lives with a chronic virus (bacteriophage) that facilitates nitrogen metabolism. Nitrogen cycling by bacteria is an essential process that frees up nitrogen for building into nucleic acids, amino acids and proteins -- the building blocks of life.
"Until recently, most research on the Planctomycetes family of bacteria has focused on strains in freshwater and shallow ocean environments, because of the logistical difficulties associated with sampling and cultivating deep-sea strains," says lead author Rikuan Zheng, a research associate at the Institute of Oceanology, Chinese Academy of Sciences, Beijing, China, and the National Laboratory for Marine Science and Technology, Qingdao, China. "Most Planctomycetes bacteria have been isolated using growth media that are nutritionally poor, so we wanted to see if using a nutrient-rich medium would make it possible to culture and further characterise members of this poorly understood family."
To learn more about this new species, the team studied its growth and how it multiplies. They found that, unlike other Planctomycetes family members, Poriferisphaera hetertotrophicis grows better in nutrient-rich media and multiplies via a budding mechanism, where parent cells create outgrowth buds that develop into daughter cells.