Complete genome of Polaromonas vacuolata KCTC 22033T isolated from beneath Antarctic Sea ice

Polaromonas vacuolata KCTC 22033(T) is an obligate aerobic, Gram-negative, psychrophilic and rod-shaped bacterium isolated from beneath the sea ice off the coast of the Palmer Peninsula, Anvers Islands, Antarctica. P. vacuolata is the type species of Polaromonas genus and the first example of gas vacuolate Betaproteobacteria isolated from marine habitats. Here, we report a complete genome of P. vacuolata KCTC 22033(T) , which consists of 3,837,686 bp (G + C content of 52.07%) with a single chromosome, 3461 protein-coding genes, 56 tRNAs and 6 rRNA opemns. Genomic analysis revealed the presence of genes involved in bacterial adaptation under saline conditions, cold adaptation via the production of gas vesicles and cell adhesion proteins, and a photoheterotrophic lifestyle when challenged by starvation. Intriguingly, several of these genes were likely acquired from species outside the Polaromonas genus. The genomic information therefore describes the unique evolution and adaptation of P. vacuolata to its extraordinary habitat, i.e., beneath the Antarctic sea ice.

Automated summary

Polaromonas vacuolata KCTC 22033(T) is a unique bacterium isolated from beneath the Antarctic sea ice, showing genomic features related to adaptation to salinity, cold, and starvation, as well as genes likely acquired from species outside its genus.