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bioRxiv · 10.1101/2025.06.13.657406

Genomic adaptations of novel halotolerant bacteria from extreme North Greenland

Salinas-Garcia, M. A.·Prieme, A.
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Abstract

Peary Land, northern-most Greenland, is a cold desert region whose soil microbiome remains underexplored. This is the first study to explore the halotolerant soil microbiome of this region with culture-dependent methods. Forty-nine taxonomically diverse bacterial isolates were obtained from dry biological soil crust, surface soil and permafrost soil. Nine isolates were selected for whole genome sequencing; these genomes showed adaptations to their cold, saline native environment, such as cold shock proteins and a large number of osmoprotectant transporters. The genomes also contained several biosynthetic gene clusters, including a large variety of clusters involved in the production of antimicrobial compounds. Furthermore, most of the sequenced genomes showed low digital DNA-DNA hybridisation to their closest relatives, suggesting that they represent novel species. Overall, this study demonstrates the unexplored potential of High Arctic deserts as a source of novel halotolerant bacteria and their secondary metabolites.

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Salinas-Garcia, M. A., Prieme, A.. 2025-06-13. Genomic adaptations of novel halotolerant bacteria from extreme North Greenland. https://doi.org/10.1101/2025.06.13.657406

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