Description of Polystyrenella longa gen. nov., sp. nov., isolated from polystyrene particles incubated in the Baltic Sea

Planctomycetes occur in almost all aquatic ecosystems on earth. They have a remarkable cell biology, and members of the orders Planctomycetales and Pirellulales feature cell division by polar budding, perform a lifestyle switch from sessile to motile cells and have an enlarged periplasmic space. Here, we characterise a novel planctomycetal strain, Pla110$^{τ}$, isolated from the surface of polystyrene particles incubated in the Baltic Sea. After phylogenetic analysis, the strain could be placed in the family Planctomycetaceae. Strain Pla110$^{τ}$ performs cell division by budding, has crateriform structures and grows in aggregates or rosettes. The strain is a chemoheterotroph, grows under mesophilic and neutrophilic conditions, and exhibited a doubling time of 21 h. Based on our phylogenetic and morphological characterisation, strain Pla110$^{τ}$ (DSM 103387$^{τ}$ = LMG 29693$^{τ}$) is concluded to represent a novel species belonging to a novel genus, for which we propose the name Polystyrenella longa gen. nov., sp. nov.